The Application of Probe-Based Confocal Laser Endomicroscopy as a Diagnostic Tool in Choledochoscopic Gallbladder-Preserving Surgery.

BACKGROUND AND AIMS: Choledochoscopic gallbladder-preserving surgery (CGPS) has the advantage of treating benign gallbladder diseases on the premise of gallbladder preservation. However, it has no reliable preoperative diagnosis if the gallbladder is benign. Probe-based confocal laser endomicroscopy (pCLE) can obtain real-time and clear endoscopic images at the cell level in vivo. It is widely used in the diagnosis of digestive system diseases, but not in gallbladder diseases yet. We applied these two technologies in a complementary way into the diagnosis of gallbladder diseases and thereby lifted the reliability of CGPS. METHODS: We retrospectively analyzed the total 28 patients with the indication of CGPS with intraoperative pCLE scan referred to the Second Affiliated Hospital of Baotou Medical College between October 2019 and July 2020. The intraoperative pCLE results were compared with the postoperative pathology in various gallbladder diseases. RESULTS: We compared the intraoperative pCLE diagnosis with the postoperative pathological diagnosis and found a complete match without exception in both sensitivity and specificity. CONCLUSIONS: Based on our investigation, pCLE can provide the same accuracy as the traditional pathology in the diagnosis of gallbladder diseases with the additional advantages like noninvasive, real time, and instancy. This study serves to validate the correlation between CLE and histology. It holds a broad prospect in the application of pCLE as an intraoperative diagnosis in CGPS.

TNF antagonizes CCN1 in apoptosis in esophageal adenocarcinoma.

TNF signaling mostly supports cell growth by activating NFκB and only induces cell death when NFκB activation fails. CCN1 is a matricellular protein that has been reported capable to convert TNF from a pro-survival factor into a stimulus for cell death without interfering with NFκB signaling. In this study, we examined the relationship between CCN1 and TNF in the context of esophageal adenocarcinoma and found that CCN1 did not help TNF to induce cell death when they were together, instead, it inhibited TNF expression, as well as TNF-induced JNK activation and apoptosis. CCN1 induced apoptosis in the cancer cells by itself through upregulation of TRAIL and its death receptors. The presence of TNF significantly lowered CCN1 expression and its capability in apoptosis induction. Furthermore, we found that CCN1 boosted ADAM17-mediated cleavage of TNF receptors through ITGA11 and the soluble decoy receptors generated by this action neutralized TNF activity. Taken together, CCN1 and TNF antagonize each other in esophageal cancer cells.

TNF upregulates peptidoglycan recognition protein 1 in esophageal cancer cells to clear the path to its signaling: Making the "enemy" a friend.

TNF, CCN1, and peptidoglycan recognition protein 1 (PGLYRP1) are often found together in the inflammatory tissue. While TNF and CCN1 promote tissue regeneration, PGLYRP1 protects it from bacterial infection. In fibroblasts, CCN1 was reported to support TNF in apoptosis induction while PGLYRP1 was found to compete with TNF for binding to TNFR1. When PGLYRP1 binds to TNFR1 by itself, it silences the receptor, but if HSP70 joins them, it leads to cell death. In cancer cells, however, CCN1 was found to antagonize TNF signaling by increasing the extracellular pool of TNFR1. In this study, we assessed their relationship in the esophageal cancer cells and found a more complex liaison among them. At first, TNF highly upregulated PGLYRP1 expression but downregulated CCN1. Secondly, PGLYRP1 bound TNFR1 and HSP70 both intracellularly and extracellularly, but TNF only promoted their extracellular interaction. Lastly, the knockdown of PGLYRP1 impaired TNF signaling. Taken together, this study shows that CCN1 interrupts TNF signaling by increasing the extracellular TNFR1 species while TNF fights back by upregulating PGLYRP1 to absorb them.

The Role of CCN1 in Esophageal Adenocarcinoma: What We Have Learned From the Lab.

Background: Esophageal cancer is one of the most common and deadliest cancers in the world, particularly esophageal adenocarcinoma. There has never been a special drug to treat it.Purpose: This article summarizes the work that we have done in our laboratory about the role of CCN1 in esophageal cancer and gives a new perspective of CCN1 biology.Research Design: This is a review article. Study Sample: The work was done using validated cell lines and fixed human tissue slides.Data Collection and Analysis: This is a review article, therefore, no data collection or analysis was involved.Results: CCN1 is a matricellular protein supporting adhesion, migration, and survival in normal cells, but in the esophageal cancer cells, it induces TRAIL-mediated apoptosis. CCN1 promotes TRAIL and its death receptor expression but downregulates the decoy receptors and survivin in a p53-dependant manner. It was thought that CCN1 relies on TNF to induce apoptosis, but our study found that these two molecules antagonize each other. CCN1 promotes TNFR1 cleavage and uses the soluble product to block TNF signaling, while TNF upregulates PGLYRP1 to overcome this obstacle because PGLYRP1 is a secreted protein that competes with TNF for TNFR1 binding. As a result, when CCN1 and TNF are present together in the vicinity of esophageal tumors, they cancel each other out.Conclusions: Based on our laboratory study, CCN1 has much potential to be a candidate for the treatment of esophageal cancer.

From Apoptosis to Necroptosis: The Death Wishes to Cancer.

DNA mutation is a common event in the human body, but in most situations, it is fixed right away by the DNA damage response program. In case the damage is too severe to repair, the programmed cell death system will be activated to get rid of the cell. However, if the damage affects some critical components of this system, the genetic scars are kept and multiply through mitosis, possibly leading to cancer someday. There are many forms of programmed cell death, but apoptosis and necroptosis represent the default and backup strategy, respectively, in the maintenance of optimal cell population as well as in cancer prevention. For the same reason, the ideal approach for cancer treatment is to induce apoptosis in the cancer cells because it proceeds 20 times faster than tumor cell proliferation and leaves no mess behind. Induction of necroptosis can be the second choice in case apoptosis becomes hard to achieve, however, necroptosis finishes the job at a cost-inflammation.

Long non-coding RNA HNF1A-AS1 upregulates OTX1 to enhance angiogenesis in colon cancer via the binding of transcription factor PBX3.

Colon cancer shows characteristics of metastasis, which is associated with angiogenesis. Increasing evidence highlights long non-coding RNAs (lncRNAs) as important participants in angiogenesis of cancers, including colon cancer. Hence, this study investigated the role of HNF1A-AS1 in angiogenesis of colon cancer. RT-qPCR and Western blot analysis were applied to detect HNF1A-AS1 and OTX1 expression in colon cancer tissues and cell lines. Then the interactions among HNF1A-AS1, PBX3, OTX1 and ERK/MAPK pathway were evaluated with RNA pull-down, RIP, ChIP and dual-luciferase reporter gene assays. Next, HCT116 and SW620 cells were treated with si-HNF1A-AS1 and/or oe-OTX1 plasmids to assess the effects of HNF1A-AS1 and OTX1 on angiogenesis, which was further evaluated in nude mice injected with SW620 cells transfected with sh-HNF1A-AS1 or sh-OTX1 lentivirus. HNF1A-AS1 and OTX1 were highly expressed in colon cancer. Silencing of HNF1A-AS1 inhibited angiogenesis of colon cancer in vivo and in vitro. HNF1A-AS1 increased the OTX1 expression by binding to transcription factor PBX3 to promote angiogenesis in colon cancer. Further, HNF1A-AS1 upregulated OTX1 to activate the ERK/MAPK pathway. Altogether, our findings identified HNF1A-AS1 as a tumor-promoting RNA in colon cancer, which could serve as a potential therapeutic target for colon cancer treatment.

Long non-coding RNA LINC00858 inhibits colon cancer cell apoptosis, autophagy, and senescence by activating WNK2 promoter methylation.

Accumulating evidence shows the involvement of long non-coding RNAs (lncRNAs) in tumorigenesis of many types of human cancers. However, the role of LINC00858 in colon cancer has not been fully elucidated. Therefore, we investigated the involvement of LINC00858 in the progression of colon cancer and identified its downstream targets. After examining the expression of LINC00858 in colon cancer tissues and cell lines, we then identified the possible interaction between LINC00858 and WNK lysine deficient protein kinase 2 (WNK2) by fluorescence in situ hybridization, RNA immunoprecipitation, chromatin immunoprecipitation, and RNA pull-down assays. Next, the role of the LINC00858/WNK2 axis was explored by evaluating the apoptosis, autophagy, and senescence of colon cancer cells in vitro after ectopic expression and depletion experiments in HCT116 cells. Moreover, a mouse xenograft model of HCT116 cells was established to verify the function of the LINC00858/WNK2 axis in vivo. There was high expression of LINC00858 and low expression of WNK2 in colon cancer tissues and cell lines. Silencing of LINC00858 promoted apoptosis, senescence, and autophagy in colon cancer cells. Additionally, the enrichment of WNK2 was promoted when LINC00858 bound to DNA methyltransferases. Furthermore, in vivo assays demonstrated that silencing of LINC00858 resulted in inhibited tumor growth by upregulating WNK2. In summary, LINC00858 acts as a tumor-promoting lncRNA in colon cancer by downregulating WNK2. Our results may provide novel targets for the treatment for colon cancer.

Association analysis between SNPs in LATS1 and LATS2 and non-cardia gastric cancer.

BACKGROUND: Many studies have found that large tumor suppressor kinase 1 (LATS1) and LATS2 play important roles in many diseases, but studies have been rare on the relationship between these genes and non-cardia gastric cancer (GC). We performed a case-control association study to investigate the associations between single nucleotide polymorphisms (SNPs) in LATS1 and LATS2 genes and Helicobacter pylori (H. pylori) infection as well as the risk of non-cardia GC. METHODS: First, H. pylori infection was determined by the serological test using enzyme-linked immunoassay. Then genotyping of SNPs was performed for 808 samples by the Taqman method. Finally, unconditional logistic regression was used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for age and gender, for the association of each SNP with the infection of H. pylori, the risk of non-cardia gastric cancer, as well as the expression of LATS1 and LATS2 proteins in non-cardia GC tissues, using the codominant, dominant, recessive, overdominant, and log-additive inheritance models, respectively. RESULTS: The statistical results showed that LATS2 rs9552315 was associated with H. pylori infection, and the CC + CT genotype could reduce the risk of H. pylori infection (odds ratio [OR]: 0.549, 95% confidence interval [CI]: 0.339-0.881, P < 0.05) compared with the TT genotype in a dominant model. LATS1 rs9393175 was associated with the risk of non-cardia GC, and the AG genotype reduced the risk of non-cardia GC (OR: 0.702, 95% CI: 0.516-0.952, P < 0.05) compared with the GG + AA genotype in an overdominant model. LATS2 rs9509492 was associated with the risk of GC in an log-additive model. No associations were found between five SNPs and expression of LATS1 and LATS2 proteins in non-cardia GC tissue. CONCLUSIONS: LATS2 rs9552315 CT genotype may be a protective factor against infection of H. pylori. LATS1 rs9393175 AG genotype and LATS2 rs9509492 GG genotype may be protective factors for non-cardia GC.

CCN1 induces apoptosis in esophageal adenocarcinoma through p53-dependent downregulation of survivin.

Many cancer drugs have been developed to control tumor growth by inducing cancer cell apoptosis. However, several intracellular barriers could fail this attempt. One of these barrier is high expression of survivin. Survivin can interfere caspase activation and thereby abort apoptosis. In this study, we found that CCN1 suppressed the survivin expression in tumor cells of esophageal adenocarcinoma (EAC) and thus allowed apoptosis to finish. Furthermore, we demonstrated that this downregulation was dependent on p53 phosphorylation at Ser20, and CCN1 induced EAC cell apoptosis through the activation of p53.

Overexpression of CCN1 in Het1A cells attenuates bile-induced esophageal metaplasia through suppressing non-canonical NFκB activation.

GERD is the most common gastrointestinal diagnosis given during office visit. People who suffer from a long history of GERD eventually develop Barrett's esophagus, a premalignant intestinal metaplasia due to NFκB activation. Previous studies focused on the contribution of TNF-triggered canonical NFκB pathway to this event. In this study, we demonstrated in vitro that it was LTA, rather than TNF, initiated canonical NFκB activation at the beginning of acid/bile attacks, but later it switched to CD40-activated non-canonical pathway, which played a bigger part in esophageal metaplasia. CCN1 attenuated this cellular transformation by suppressing CD40 and its associated proteins involved in non-canonical signaling.

Synthesis of Acyl Azides from 1,3-Diketones via Oxidative Cleavage of Two C-C Bonds.

A metal-free PhI(OAc)2-mediated method for the synthesis of acyl azides through oxidative cleavage of 1,3-diketones is described. This method is shown to have a broad substrate scope, providing a useful tool for multiproduct synthesis in a single procedure. A possible reaction pathway is proposed based on mechanistic studies.

CCN1 sensitizes esophageal cancer cells to TRAIL-mediated apoptosis.

TRAIL is one of the best anti-cancer molecules in our body. It kills a variety of cancer cells that are resistant to conventional chemotherapy, without causing much negative impact on normal cells, because its death receptors are almost exclusively found on cancer cells. However, some cancer cells are not sensitive to TRAIL treatment, even though they express its death receptors. A second molecule is needed to help TRAIL to complete its mission. Finding such molecules now becomes a top priority in cancer research. Our study shows that CCN1 is such a molecule. CCN1 was highly expressed in the esophageal epithelium of the patients suffering from gastroesophageal reflux disease, but faded away as the situation worsened towards adenocarcinoma. Treating the tumor cells with CCN1 resulted in apoptosis, while the same treatment to the normal cells only nourished cell growth. It was TRAIL that mediated this process. Apparently, CCN1 altered the expression profile of TRAIL and its receptors in tumor cells, namely, activating TRAIL and its death receptors and shutting down its decoy receptors. CCN1 and TRAIL worked as a team to put the cancer cells to death, as elimination of either one failed apoptosis.

MicroRNA-128 acts as a suppressor in the progression of gastrointestinal stromal tumor by targeting B-lymphoma Mo-MLV insertion region 1.

INTRODUCTION: The critical role of microRNA-128 (miR-128) in gastrointestinal-related diseases has been documented. In the current study, we tried to clarify the specific role miR-128 in gastrointestinal stromal tumor (GIST) and the underlying mechanism. METHODS: Differentially expressed genes in GIST were identified following bioinformatics analysis. Then, expression patterns of miR-128 and B-lymphoma Mo-MLV insertion region 1 (BMI-1) in clinical tissue samples and cell lines were characterized, followed by validation of their correlation. GIST-T1 cells were selected and transfected with different mimic, inhibitor, or siRNA plasmids, after which the biological functions were assayed. RESULTS: We identified low miR-128 and high BMI-1 expression in GIST tissues of 78 patients and 4 GIST cell lines. Ectopic expression of miR-128 or silencing of BMI-1 suppressed the malignant potentials of GIST-T1 cells. As a target of miR-128, BMI-1 re-expression could partly counteract the suppressive effect of miR-128 on the malignancy of GIST-T1 cells. CONCLUSION: Our study provided evidence that miR-128-mediated silencing of BMI-1 could prevent malignant progression of GIST, highlighting a promising anti-tumor target for combating GIST.

Mouse auditory cortex sub-fields receive neuronal projections from MGB subdivisions independently.

Mouse auditory cortex is composed of six sub-fields: primary auditory field (AI), secondary auditory field (AII), anterior auditory field (AAF), insular auditory field (IAF), ultrasonic field (UF) and dorsoposterior field (DP). Previous studies have examined thalamo-cortical connections in the mice auditory system and learned that AI, AAF, and IAF receive inputs from the ventral division of the medial geniculate body (MGB). However, the functional and thalamo-cortical connections between nonprimary auditory cortex (AII, UF, and DP) is unclear. In this study, we examined the locations of neurons projecting to these three cortical sub-fields in the MGB, and addressed the question whether these cortical sub-fields receive inputs from different subsets of MGB neurons or common. To examine the distributions of projecting neurons in the MGB, retrograde tracers were injected into the AII, UF, DP, after identifying these areas by the method of Optical Imaging. Our results indicated that neuron cells which in ventral part of dorsal MGB (MGd) and that of ventral MGB (MGv) projecting to UF and AII with less overlap. And DP only received neuron projecting from MGd. Interestingly, these three cortical areas received input from distinct part of MGd and MGv in an independent manner. Based on our foundings these three auditory cortical sub-fields in mice may independently process auditory information.

Clinical characteristics and prognosis of non-APAP drug-induced acute liver failure: a large multicenter cohort study.

BACKGROUND: There is growing recognition of natural history, complications, and outcomes of patients who develop non-acetaminophen (APAP) drug-induced acute liver failure (ALF). To clarify high-risk factors and develop a nomogram model to predict transplant-free survival (TFS) in patients with non-APAP drug-induced ALF. METHODS: Patients with non-APAP drug-induced ALF from 5 participating centers were retrospectively analyzed. The primary endpoint was 21-day TFS. Total sample size was 482 patients. RESULTS: Regarding causative agents, the most common implicated drugs were herbal and dietary supplements (HDS) (57.0%). The hepatocellular type (R ≥ 5) was the main liver injury pattern (69.0%). International normalized ratio, hepatic encephalopathy grades, the use of vasopressor, N-acetylcysteine, or artificial liver support system were associated with TFS and incorporated to construct a nomogram model (drug-induced acute liver failure-5, DIALF-5). The AUROC of DIALF-5 for 7-day, 21-day, 60-day, and 90-day TFS in the internal cohort were 0.886, 0.915, 0.920, and 0.912, respectively. Moreover, the AUROC of DIALF-5 for 21-day TFS had the highest AUROC, which was significantly higher than 0.725 of MELD and 0.519 of KCC (p < 0.05), numerically higher than 0.905 of ALFSG-PI but without statistical difference (p > 0.05). These results were successfully validated in the external cohort (147 patients). CONCLUSIONS: Based on easily identifiable clinical data, the novel DIALF-5 model was developed to predict transplant-free survival in non-APAP drug-induced ALF, which was superior to KCC, MELD and had a similar prediction performance to ALFSG-PI but is more convenient, which can directly calculate TFS at multiple time points.

Machine learning-based automated sponge cytology for screening of oesophageal squamous cell carcinoma and adenocarcinoma of the oesophagogastric junction: a nationwide, multicohort, prospective study.

BACKGROUND: Oesophageal squamous cell carcinoma and adenocarcinoma of the oesophagogastric junction have a dismal prognosis, and early detection is key to reduce mortality. However, early detection depends on upper gastrointestinal endoscopy, which is not feasible to implement at a population level. We aimed to develop and validate a fully automated machine learning-based prediction tool integrating a minimally invasive sponge cytology test and epidemiological risk factors for screening of oesophageal squamous cell carcinoma and adenocarcinoma of the oesophagogastric junction before endoscopy. METHODS: For this multicohort prospective study, we enrolled participants aged 40-75 years undergoing upper gastrointestinal endoscopy screening at 39 tertiary or secondary hospitals in China for model training and testing, and included community-based screening participants for further validation. All participants underwent questionnaire surveys, sponge cytology testing, and endoscopy in a sequential manner. We trained machine learning models to predict a composite outcome of high-grade lesions, defined as histology-confirmed high-grade intraepithelial neoplasia and carcinoma of the oesophagus and oesophagogastric junction. The predictive features included 105 cytological and 15 epidemiological features. Model performance was primarily measured with the area under the receiver operating characteristic curve (AUROC) and average precision. The performance measures for cytologists with AI assistance was also assessed. FINDINGS: Between Jan 1, 2021, and June 30, 2022, 17 498 eligible participants were involved in model training and validation. In the testing set, the AUROC of the final model was 0·960 (95% CI 0·937 to 0·977) and the average precision was 0·482 (0·470 to 0·494). The model achieved similar performance to consensus of cytologists with AI assistance (AUROC 0·955 [95% CI 0·933 to 0·975]; p=0·749; difference 0·005, 95% CI, -0·011 to 0·020). If the model-defined moderate-risk and high-risk groups were referred for endoscopy, the sensitivity was 94·5% (95% CI 88·8 to 97·5), specificity was 91·9% (91·2 to 92·5), and the predictive positive value was 18·4% (15·6 to 21·6), and 90·3% of endoscopies could be avoided. Further validation in community-based screening showed that the AUROC of the model was 0·964 (95% CI 0·920 to 0·990), and 92·8% of endoscopies could be avoided after risk stratification. INTERPRETATION: We developed a prediction tool with favourable performance for screening of oesophageal squamous cell carcinoma and adenocarcinoma of the oesophagogastric junction. This approach could prevent the need for endoscopy screening in many low-risk individuals and ensure resource optimisation by prioritising high-risk individuals. FUNDING: Science and Technology Commission of Shanghai Municipality.

Timing of endoscopy for acute variceal bleeding in patients with cirrhosis (CHESS1905): A nationwide cohort study.

BACKGROUND: Endoscopy plays an important role in the management of acute variceal bleeding (AVB) in patients with cirrhosis. This study aimed at determining the optimal endoscopy timing for cirrhotic AVB. METHODS: Patients with cirrhosis with AVB across 34 university hospitals in 30 cities from February 2013 to May 2020 who underwent endoscopy within 24 hours were included in this study. Patients were divided into an urgent endoscopy group (endoscopy <6 h after admission) and an early endoscopy group (endoscopy 6-24 h after admission). Multivariable analysis was performed to identify risk factors for treatment failure. Primary outcome was the incidence of 5-day treatment failure. Secondary outcomes included in-hospital mortality, need for intensive care unit, and length of hospital stay. A propensity score matching analysis was performed. In addition, we performed an analysis, in which we compared the 5-day treatment failure incidence and the in-hospital mortality among patients with endoscopy performed at <12 hours and 12-24 hours. RESULTS: A total of 3319 patients were enrolled: 2383 in the urgent endoscopy group and 936 in the early endoscopy group. After propensity score matching, on multivariable analysis, Child-Pugh class was identified as an independent risk factor for 5-day treatment failure (HR, 1.61; 95% CI: 1.09-2.37). The incidence of 5-day treatment failure was 3.0% in the urgent endoscopy group and 2.9% in the early group ( p = 0.90). The in-hospital mortality was 1.9% in the urgent endoscopy group and 1.2% in the early endoscopy group ( p = 0.26). The incidence of need for intensive care unit was 18.2% in the urgent endoscopy group and 21.4% in the early endoscopy group ( p = 0.11). The mean length of hospital stay was 17.9 days in the urgent endoscopy group and 12.9 days in the early endoscopy group ( p < 0.05). The incidence of 5-day treatment failure in the <12-hour group was 2.3% and 2.2% in the 12-24 hours group ( p = 0.85). The in-hospital mortality was 2.2% in the <12-hour group and 0.5% in the 12-24 hours group ( p < 0.05). CONCLUSIONS: The data suggest that performance of endoscopy within 6-12 or within 24 hours of presentation among patients with cirrhosis with AVB led to similar treatment failure outcomes.

CCN1 suppresses cell proliferation of esophageal squamous cell carcinoma through amyloid precursor protein without DR6 participation.

Esophageal cancer is commonly seen as either squamous cell carcinoma (ESCC) or adenocarcinoma (EAC), two very different cancers. CCN1 is a matricellular protein that induces apoptosis in EAC cells through upregulation of DR5, a death receptor, while its role in ESCC is unclear. DR6 is another death receptor, which has been reported to induce apoptosis, necroptosis, or pyroptosis in various cell systems with or without the engagement of its putative ligand amyloid precursor protein (APP). In this study, we found that CCN1 and DR6 were both highly expressed in ESCC but downregulated in EAC. Overexpression of CCN1 in ESCC cells inhibited cell proliferation through upregulation of APP and its association with p53 without DR6 involvement. Overexpression of APP stopped cell growth, but overexpression of DR6 did not affect cell growth or cell death whatsoever.

The effect of polymer stiffness on magnetization reversal of magnetorheological elastomers.

Ultrasoft magnetorheological elastomers (MREs) offer convenient real-time magnetic field control of mechanical properties that provides a means to mimic mechanical cues and regulators of cells in vitro. Here, we systematically investigate the effect of polymer stiffness on magnetization reversal of MREs using a combination of magnetometry measurements and computational modeling. Poly-dimethylsiloxane-based MREs with Young's moduli that range over two orders of magnitude were synthesized using commercial polymers Sylgard™ 527, Sylgard 184, and carbonyl iron powder. The magnetic hysteresis loops of the softer MREs exhibit a characteristic pinched loop shape with almost zero remanence and loop widening at intermediate fields that monotonically decreases with increasing polymer stiffness. A simple two-dipole model that incorporates magneto-mechanical coupling not only confirms that micrometer-scale particle motion along the applied magnetic field direction plays a defining role in the magnetic hysteresis of ultrasoft MREs but also reproduces the observed loop shapes and widening trends for MREs with varying polymer stiffnesses.

A small H2O-soluble ingredient of royal jelly lower cholesterol levels in liver cells by suppressing squalene epoxidase.

Excessive cholesterol in the liver is harmful for our health and may cause many diseases, such as fatty liver disease. Many studies in human and animal models have reported that royal jelly (RJ) can be used to treat atherosclerosis. However, the real mechanisms behind this action is unclear. In this study, we investigated the efficacy of RJ on gene expression of squalene epoxidase (SE) a major enzyme involved in cholesterol biosynthesis in HepG2 cells. We found that the expression of SE was decreased in response to RJ treatment. We also found that the origin of the RJ affected its strength. To find out the active fraction of RJ in cholesterol suppression, we separated RJ into two parts based on the molecular weights using ultrafiltration membrane. We found that the fraction <10kDa from RJ had comparable effect on SE expression, especially its water-soluble part. Taken together, we think RJ suppresses cholesterol by decreasing SE gene expression in liver. The active fraction of RJ in this action is <10kDa in water-soluble form.