Digital cholangioscopy-assisted, direct visualization-guided, radiation-free, endoscopic retrograde intervention for cholelithiasis: technical feasibility, efficacy, and safety.

BACKGROUND: Nonradiation, digital cholangioscope (DCS)-assisted endoscopic intervention for cholelithiasis has not been widely performed. For this study, we aimed to report the feasibility, efficacy, and safety of an established DCS-guided lithotomy procedure. METHODS: Data relating to biliary exploration, stone clearance, adverse events, and follow-up were obtained from 289 patients. The choledocholithiasis-related outcomes via the DCS-guided procedure were subsequently compared to those via conventional endoscopic retrograde cholangiopancreatography (ERCP). RESULTS: Biliary access was achieved in 285 patients. The technical success rate for the exploration of the common bile duct, the cystic stump, the hilar ducts, and secondary radicals was 100%. Moreover, the success rates were 98.4%, 61.7%, and 20.7%, for the exploration of the cystic duct, complete cystic duct, and gallbladder, respectively. Suspicious or confirmed suppurative cholecystitis, cholesterol polyps, and hyperplastic polyps were detected in 42, 23, and 5 patients, respectively. Stone clearance was achieved in one session in 285 (100%), 11 (100%), 13 (100%), 7 (100%), 6 (100%), and 3 (14.3%) patients with choledocholithiasis and hepatolithiasis, cystic duct stump stones, nondiffuse located intrahepatic lithiasis, a single cystic duct stone, a single gallbladder stone, and diffuse located intrahepatic lithiasis, respectively. Complete stone clearance for diffuse intrahepatic lithiasis was achieved in 19 (90.5%) patients, and fractioned re-lithotomy was performed in 16 (76.2%) patients. One patient developed mild acute cholangitis, and 12 developed mild pancreatitis. Stones recurred in one patient. Compared with conventional ERCP, DCS-guided lithotomy has the advantages of clearing difficult-to-treat choledocholithiasis and revealing concomitant biliary lesions, and this technique has fewer complications and a decreased risk of stone recurrence. CONCLUSIONS: The technical profile, efficacy, and safety of nonradiation-guided and DCS-guided lithotomy are shown in this study. We provide a feasible modality for the endoscopic removal of cholelithiasis.

Insulin-like growth factor-2 mRNA-binding protein 3 promotes cell migration, invasion, and epithelial-mesenchymal transition of esophageal squamous cell carcinoma cells by targeting zinc finger E-box-binding homeobox 1 mRNA.

The role and mechanism of insulin-like growth factor-2 mRNA-binding protein 3 (IGF2BP3) in the metastasis of esophageal squamous cell carcinoma (ESCC) remain unclear. In this study, IGF2BP3 mRNA and protein expression levels were evaluated in ESCC tissues. Small interfering RNAs (siRNAs), plasmid overexpression, and stable lentivirus transfection were used to manipulate intracellular IGF2BP3 expression levels. The role of IGF2BP3 in ESCC tumorigenesis was investigated in vitro and in vivo. IGF2BP3 target transcripts were detected, and the acetylation effect ratios of the IGF2BP3 promoter region by H3K27ac were determined. IGF2BP3 mRNA expression levels were significantly higher in ESCC tissues than in normal esophageal tissues. Increased IGF2BP3 expression levels were detected in node-negative ESCC tissues and correlated with greater lesion depth in ESCC. Overexpression of IGF2BP3 promoted ESCC development in vitro and in vivo, and IGF2BP3 knockdown caused an opposite effect. IGF2BP3 was found to directly bind to the zinc finger E-box-binding homeobox 1 (Zeb1) mRNA, and the downregulation of IGF2BP3 reduced the stability of Zeb1 mRNA. IGF2BP3 induced epithelial-mesenchymal transition in ESCC cells in a Zeb1-dependent manner. IGF2BP3 was transcriptionally activated in ESCC cell lines via H3K27 acetylation. Our results demonstrate that IGF2BP3 plays a vital role in ESCC cell proliferation, invasion, and metastasis and is a potential therapeutic target for treating ESCC.

Rhodium(III)-catalysed redox neutral alkylation of 3-arylbenzo[d]isoxazoles: easy access to substituted succinimides.

A convenient method for the alkylation of 3-arylbenzo[d]isoxazoles with maleimides under redox-neutral conditions has been developed, giving a series of substituted succinimides in up to 99% yield. This transformation is highly selective to give succinimides, and Heck-type products are successfully avoided. This protocol features 100% atom-economy and broad substrate tolerance, and provides a novel strategy for the synthesis of diverse succinimides and an opportunity for the succinylation of protein medication and for pharmacologists to discover first-in-class drugs.

Radiation-free endoscopic papillectomy for ampullary adenoma: experience from a Chinese tertiary hospital.

BACKGROUND: Conventional endoscopic papillectomy (ESP) for ampullary adenoma is performed as a hybrid endoscopy and fluoroscopy guided procedure. In this study, we report our preliminary experience of non-radiation ESP. METHODS: The present method includes endoscopic snare resection, non-radiation endoscopic biliary and pancreatic stenting and endoclipping. Data from ten patients who underwent non-radiation ESP due to ampullary adenoma were collected. Procedure details, adverse events and follow-up were analyzed. RESULTS: Complete resection was accomplished in all patients, with en bloc resection and piecemeal resection in nine and one patient(s), respectively. Both biliary and pancreatic stenting and biliary stenting alone were achieved in eight and two patients, respectively. Endoclipping was performed in all patients. Hyperleukocytosis and hyperamylasemia occurred in two and one patient(s), respectively. No other complications occurred. No lesion residual or recurrence occurred during follow-up. CONCLUSIONS: Radiation-free ESP can be technically feasible and safely executed by experienced endoscopists. Our study provides a novel strategy for endoscopic resection of major papilla adenoma.

Study protocol for artificial intelligence-assisted sponge cytology as pre-endoscopy screening for early esophegeal squmaous epithelial lesions in China.

BACKGROUND: Endoscopic screening is the widely accepted screening strategy for esophageal squmaous cell carcinoma (ESCC). However, massive endoscopic screening is expensive and not cost-efficient, and novel pre-endoscopy detection used as a preliminary screening method arouses new concerns. We are planning to launch an artificial intelligence (AI) assisted sponge cytology for detecting esophageal squmaous high-grade intraepithelial neoplasia (HGIN) and above lesions. The aim of this trail is to investigate the efficiency of AI-assisted sponge cytology in population-based screening of early esophageal squmaous epithelial lesions. METHODS: The study will be prospectively conducted in five regions with a high prevalence of ESCC. AI-assisted sponge cytology and endoscopic examination will be sequentially performed. Based on our previous data, at least 864 patients with esophageal HGIN and above lesions are needed to achieve enough statistical power. And, a calculated 112,500 individuals with high risks of ESCC will be recruited. In the first stage, each 24,000 participants who meet the inclusion criteria will be recruited on a voluntary basis. Setting pathological results as standard reference, diagnostic threshold and according performance of AI-assisted detection will be evaluated. A prediction model will be constructed by co-analyzing cytological results and relevant risk factors. Then, an external validation cohort will be used for validation of the model efficiency. Also, cost-efficiency analysis will be performed. This study protocol was registered on chineseclinicaltrial.gov (ChiCTR1900028524). DISCUSSION: Our study will determine whether this AI-assisted sponge cytology can be used as an effective pre-endoscopy detection tool for large-scale screening for ESCC in high-risk areas.

Comparison of 180° anti-reflux mucosectomy versus 270° anti-reflux mucosectomy for treatment of refractory gastroesophageal reflux disease: a retrospective study.

BACKGROUND: Anti-reflux mucosectomy (ARMS) is a novel endoscopic treatment for refractory gastroesophageal reflux disease (rGERD). Several studies have validated its safety and effectiveness, but postoperative dysphagia remains in concern. Since the influence of different resection ranges on efficacy and complications of ARMS has rarely been studied, this study aimed to compare outcomes of 180°ARMS and 270°ARMS in treatment of rGERD. METHODS: This study was conducted from August 2017 to September 2020. 39 eligible patients underwent either 180° ARMS or 270° ARMS and followed up at 6 months postoperation. Primary outcome measure was assessed by Gastroesophageal Reflux Disease Questionnaire (GERD-Q). Secondary outcomes included quality of life, PPI use, gastroesophageal flap valve grade, presence of reflux esophagitis, acid exposure time (AET), distal contractile integral (DCI), and integrated relaxation pressure (IRP) measured by high-resolution manometry (HRM) and complication rate. Per-protocol analysis was performed. RESULTS: Among 39 patients, 18 underwent 180° ARMS, while 21 underwent 270° ARMS. At postoperative 6 months follow-up period, primary outcome showed no significant difference between two groups (p = 0.34). Similarly, no significant difference was demonstrated between groups regarding most secondary outcomes except for fewer complaints of newly dysphagia in 180° ARMS group. No other serious complications were observed in both groups. CONCLUSION: Although 180° ARMS and 270° ARMS could be equally effective for treatment of rGERD, 180° ARMS might be more recommended due to lower incidence of newly post-procedural dysphagia.

LncRNA SNHG16 promotes development of oesophageal squamous cell carcinoma by interacting with EIF4A3 and modulating RhoU mRNA stability.

BACKGROUND: Numerous studies have revealed that long noncoding RNAs (lncRNAs) are closely related to the development of many diseases and carcinogenesis. However, their specific biological function and molecular mechanism in oesophageal squamous cell carcinoma (ESCC) remains unclear. METHODS: RNA-Seq was performed to determine the differential expressions of lncRNAs in ESCC, and the level of SNHG16 expression was detected in ESCC and intraepithelial neoplasia (IEN) samples. In vitro and in vivo experiments were performed to explore the role of SNHG16 and the interaction of EIF4A3 and Ras homologue family member U (RhoU) signalling. RESULTS: One hundred and seventy-five upregulated and 134 downregulated lncRNAs were identified by RNA-Seq. SNHG16 was highly expressed in ESCC and intraepithelial neoplasia (IEN) samples, and its expression level was correlated with tumour differentiation and T stage. Overexpression of SNHG16 can facilitate ESCC cell proliferation and metastasis. Mechanistically, we noticed that SNHG16 could bind RNA binding protein (RBP)-eukaryotic translation initiation factor (EIF4A3) and interact with it to form a complex. Importantly, the coalition of SNHG16 and EIF4A3 ultimately regulated Ras homologue family member U (RhoU). SNHG16 modulated RhoU expression by recruiting EIF4A3 to regulate the stability of RhoU mRNA. Knockdown of RhoU further alleviated the effect of the SNHG16 oncogene in ESCC cells. CONCLUSIONS: The newly identified SNHG16-EIF4A3-RhoU signalling pathway directly coordinates the response in ESCC pathogenesis and suggests that SNHG16 is a promising target for potential ESCC treatment.

Feasibility and Accuracy of Artificial Intelligence-Assisted Sponge Cytology for Community-Based Esophageal Squamous Cell Carcinoma Screening in China.

INTRODUCTION: Screening is the pivotal strategy to relieve the burden of esophageal squamous cell carcinoma (ESCC) in high-risk areas. The cost, invasiveness, and accessibility of esophagogastroduodenoscopy (EGD) necessitate the development of preliminary screening methods. METHODS: Residents aged 40-85 years were recruited in a high-risk area of ESCC. Esophageal cells were collected using an approved novel capsule sponge, and cytology slides were scanned by a trained artificial intelligence (AI) system before cytologists provided confirmation. Atypical squamous cell or more severe diagnosis was defined as positive cytology. AI-based abnormal cell counts were also reported. EGD was performed subsequently with biopsy as needed. Diagnostic accuracy, adverse events, and acceptability of cytology testing were assessed. Esophageal high-grade lesions (ESCC and high-grade intraepithelial neoplasia) were the primary target lesions. RESULTS: In total, 1,844 participants were enrolled, and 20 (1.1%) high-grade lesions were confirmed by endoscopic biopsy. The AI-assisted cytologist-confirmed cytology showed good diagnostic accuracy, with a sensitivity of 90.0% (95% confidence interval [CI], 76.9%-100.0%), specificity of 93.7% (95% CI, 92.6%-94.8%), and positive predictive value of 13.5% (95% CI, 7.70%-19.3%) for detecting high-grade lesions. The area under the receiver operation characteristics curve was 0.926 (95% CI, 0.850-1.000) and 0.949 (95% CI, 0.890-1.000) for AI-assisted cytologist-confirmed cytology and AI-based abnormal cell count, respectively. The numbers of EGD could be reduced by 92.5% (from 99.2 to 7.4 to detect 1 high-grade lesion) if only cytology-positive participants were referred to endoscopy. No serious adverse events were documented during the cell collection process, and 96.1% participants reported this process as acceptable. DISCUSSION: The AI-assisted sponge cytology is feasible, safe, and acceptable for ESCC screening in community, with high accuracy for detecting esophageal squamous high-grade lesions.

C-C Bond Cleavage Initiated Cascade Reaction of ß-Enaminones: One-Pot Synthesis of 5-Hydroxy-1H-pyrrol-2(5H)-ones.

An unprecedented C(CO)-C(Ar) bond cleavage of ß-enaminones has been realized under mild and transition-metal-free conditions. The cascade transformation based on this C-C bond cleavage involves 1,3-O/C migration and aerobic hydroxylation and leads to various 5-hydroxy-1H-pyrrol-2(5H)-ones with broad functional group tolerance. The application of this methodology has been showcased by preparing 5-alkoxy-1H-pyrrol-2(5H)-one derivatives and a pyrrolo[2,1-a]isoquinolin-3-one derivative.

Radiation-free digital cholangioscopy-guided laser lithotripsy for large common bile duct stones: feasibility and technical notes.

AIMS: Although endoscopic retrograde cholangiopancreatography (ERCP) for large common bile duct (CBD) stones is facilitated by digital cholangioscopy-guided lithotripsy, it is performed by fluoroscopy guidance. Here, we report our experience of non-radiation ERCP for large CBD stones using digital cholangioscopy-guided laser lithotripsy. METHODS: Sixteen patients with large CBD stones underwent non-radiation digital cholangioscopy-guided laser lithotripsy and lithotomy. Data relevant to procedure details, adverse events, and short-term follow-up were analyzed. RESULTS: Biliary access was achieved in all patients using standard guidewire-assisted cannulation, double-guidewire technique, and transpancreatic precut in twelve, two, and two patients, respectively. Balloons of 10 mm, 8 mm, and 6 mm in diameter were applied for EPBD in 8, 2, and 6 patients, respectively. Complete stone removal in one session was achieved in all patients. One round of laser lithotripsy was needed for stone ≤ 25 mm, and three-to-five rounds were needed for stones > 25 mm or multiple stones. One or two clips were used for endoscopic clipping. The time lengths of biliary access, digital cholangioscopy-assisted laser lithotripsy and stone extraction, and whole procedure were 3.5 ± 3.2 (0.5-12) minutes, 52.5 ± 30.6 (45-97) minutes, and 76 ± 23.3 (58-106) minutes, respectively. Asymptomatic hyperleukocytose, hyperamylasemia, and mild pancreatitis were present in 1, 2, and 1 patient(s), respectively. No other complications occurred. No cholangitis or recurrent CBD stones were observed. CONCLUSION: Non-radiation digital cholangioscopy-guided laser lithotripsy is technically feasible and can be safely performed for endoscopic management of large CBD stones.

The efficacy and safety of one-stage endoscopic treatment for ascending acute cholangitis caused by choledocholithiasis with severe comorbidities.

BACKGROUND: Emergency endoscopic retrograde cholangiopancreatography (ERCP) for ascending acute cholangitis in patients with severe comorbidities is challenging. Here, we evaluated the efficacy and safety of one-stage ERCP in such patients by performing a retrospective study. METHODS: We included all patients with ascending acute cholangitis and undergoing ERCP between January 2017 and March 2019. In total, we recruited 212 patients: 74 and 138 with and without severe comorbidities, respectively. We collected and analyzed data related to basal characteristics, ERCP, and clinical outcomes. RESULTS: Elderly age (76.20 ± 9.99 years vs. 66.52 ± 8.16 years, P = 0.000), higher levels of leukocyte count (15.86 ± 2.47 × 109/ml vs. 13.49 ± 1.65 × 109/ml, P = 0.000), and serum bilirubin (3.11 ± 1.29 mg/dl vs. 1.94 ± 0.90 mg/dl, P = 0.000) were present in patients with severe comorbidities. A significantly higher proportion of these patients were severe cases (32.4% vs. 6.5%, P = 0.000), American Society of Anesthesiologists (ASA) stage V status (37.8% vs. 10.1%, P = 0.000) and had undergone general anesthesia (56.8% vs. 18.8%, P = 0.000). Successful biliary cannulation and complete stone clearance in one session were achieved in 207 and 202 patients, respectively. Mean length of hospital stay was 8.02 ± 2.71 days. Forty-three patients required ICU stay with the mean length of 3.26 ± 3.51 days. In-hospital mortality occurred in seven patients; all these patients had severe comorbidities. ERCP details, including urgent and early ERCP, biliary cannulation, complete stone clearance in one session, stent insertion, and complications were not significantly different between the two groups. Patients with severe comorbidities had a longer in-hospital stay (9.39 ± 3.15 days vs. 7.29 ± 2.11 days, P = 0.000), a higher proportion of ICU admission (45.9% vs. 6.5%, P = 0.000), and a longer ICU stay length (4.88 ± 4.37 days vs. 1.44 ± 0.52 days, P = 0.000). Our data also revealed that early diagnosis is an important predictor associated with clinical outcomes. CONCLUSIONS: One-stage ERCP is safe and effective for ascending acute cholangitis caused by choledocholithiasis. Early diagnosis is a significant predictor of clinical outcomes.

LUCAT1 promotes colorectal cancer tumorigenesis by targeting the ribosomal protein L40-MDM2-p53 pathway through binding with UBA52.

Colorectal cancer (CRC) is the third most commonly diagnosed cancer in both men and women in the USA. However, the underlying molecular mechanisms that drive CRC tumorigenesis are still not clear. Several studies have reported that long noncoding RNAs (lncRNAs) have important roles in tumor development. Here, we undertook a transcriptome microarray analysis in 6 pairs of CRC tissues and their corresponding adjacent normal tissues. A total of 1705 differentially expressed lncRNAs were detected in CRC tissues at stages I/II and III/IV (fold change greater than or equal to 2 or less than or equal to 0.5). Among them, we found that the lncRNA lung cancer-associated transcript 1 (LUCAT1) was upregulated in CRC tissues and was closely associated with poor overall survival of CRC patients, through analysis of clinical data and The Cancer Genome Atlas. Functional studies indicated that LUCAT1 promoted CRC cell proliferation, apoptosis, migration, and invasion in vitro and in vivo. Furthermore, knockdown of LUCAT1 rendered CRC cells hypersensitive to oxaliplatin treatment. Mechanistically, bioinformatic analysis indicated that low expression of LUCAT1 was associated with the p53 signaling pathway. Chromatin isolation by RNA purification followed by mass spectrometry and RNA immunoprecipitation revealed that LUCAT1 bound with UBA52, which encodes ubiquitin and 60S ribosomal protein L40 (RPL40). We found that RPL40 functions in the ribosomal protein-MDM2-p53 pathway to regulate p53 expression. Taken together, our findings indicate that suppression of LUCAT1 induces CRC cell cycle arrest and apoptosis by binding UBA52 and activating the RPL40-MDM2-p53 pathway. These results implicate LUCAT1 as a potential prognostic biomarker and therapeutic target for CRC.

[Segmented biodegradable esophageal stents in a porcine model: preclinical evaluation of degradation, complications and tissue reactions].

Objective: To evaluate the feasibility of two types of segmented biodegradable esophageal stents in treatment of refractory benign esophagus strictures. Methods: Uncovered biodegradable segmented stent and fully-covered biodegradable segmented stent were implanted into the porcine esophagus (6 for each). Data on biodegradation, complications, and tissue reactions were compared between two groups. Results: All animals kept good general conditions; no death, decreased food intake, weight loss and malnutrition were observed. No perforation, ulcer, hemorrhage, stent migration and severe complications occurred. Stents degradation commenced at week 3. Stents structure breakage and complete stents absorption occurred at week 7-8 and week 9-10 in uncovered stents. While in fully-covered stents, stents structure breakage and complete stents absorption occurred at week 8-9 and week 10-11. Hyperplasia was prominent at week 1-3 and ameliorated at week 6 after stent implantation. A longer degradation period was present in fully-covered stents than in uncovered stents, while fully-covered stents induced tissue reactions at early stage were mild. Conclusions: The application of biodegradable esophageal stents with a segmented trunk in refractory benign esophagus strictures worth further investigation. The fully-covered stent has longer degradation period, which may be more suitable for clinical use.

Evaluating long-term attachment of a novel endoclip in porcine stomachs: a prospective study of initial deployment success and clip retention rates at different regions of the stomachs.

BACKGROUND AND AIMS: Through-the-scope endoscopic clips are widely used. Several designs of endoscopic clips are marked for different applications. However, no prior reports have been published to aid in comparing success rates of clip deployment and the retention rates at different regions of the stomachs. The aims of the article were to compare success rates of clip deployment and the retention rates at different regions of the stomachs with a novel endoclip. METHODS: Upper endoscope was inserted into the stomach of five pigs under general anesthesia. In all animals, three regions of the stomachs (gastric fundus, gastric body, and gastric antrum) were chosen as the sites of clip application. Two clips of a novel type were placed along the same gastric site at a distance of 0.5-1 cm from each other. Animals had weekly endoscopies to quantitate clip retention. RESULTS: Success rates of clip deployment were 70% for gastric fundus, 100% for gastric body, and 100% for gastric antrum. Clip retention rates were significantly higher with gastric body than with gastric fundus or gastric antrum at 1-8 weeks. CONCLUSIONS: (1) For the clip device, it seems that it is difficult for the clip deployment in gastric fundus (70%) than that in the gastric body or gastric antrum (100%), but there is no statistical significance (χ (2) test, p = 0.21). (2) Clips used in the gastric body were retained significantly longer than that in the gastric fundus or gastric antrum. (3) The novel clips were safe, and no complications such as bleeding or weight loss were noted.

Copper-Catalyzed Synthesis of 2-Arylquinazolinones from 2-Arylindoles with Amines or Ammoniums.

A novel copper-catalyzed synthesis of quinazolinones from easily available 2-arylindoles and amines or ammoniums has been developed, which provided various quinazolinones in up to 99% yields for 43 examples. This strategy features tolerance of a wide range of functional groups, easily available starting materials, simple operation, mild reaction conditions, and environmental friendliness.

Copper-Catalyzed Remote Regio- and Enantioselective Yne-Allylic Substitution of Coumarins.

Chiral coumarins and their derivatives are prominent bioactive structural units present in a wide range of natural products and pharmaceutical candidates. Therefore, the development of straightforward and efficient methodologies for the synthesis of readily functionalized chiral coumarins is of significant interest. Herein we report an enantioselective copper-catalyzed yne-allylic substitution of coumarins, resulting in a highly regioselective synthesis of diverse new classes of chiral coumarin derivatives with high efficiency and excellent functional group tolerance. Subsequent versatile transformations further demonstrate the substantial synthetic potential of this strategy in the field of biochemical research.

Urgent one-stage endoscopic treatment for choledocholithiasis related moderate to severe acute cholangitis: A propensity score-matched analysis.

BACKGROUND: During emergency endoscopic retrograde cholangiopancreatography (ERCP), the safety and feasibility of performing one-stage endoscopic treatment for patients with acute cholangitis (AC) due to choledocholithiasis are unclear. AIM: To investigate the safety and feasibility of one-stage endoscopic treatment for moderate to severe AC. METHODS: We enrolled all patients diagnosed with moderate to severe cholangitis due to common bile duct stones from January 2019 to July 2023. The outcomes were compared in this study between patients who underwent ERCP within 24 h and those who underwent ERCP 24 h later, employing a propensity score (PS) framework. Our primary outcomes were intensive care unit (ICU) admission rates, ICU length of stay, and duration of antibiotic use. RESULTS: In total, we included 254 patients and categorized them into two groups based on the time elapsed between admission and intervention: The urgent group (≤ 24 h, n = 102) and the elective group (> 24 h, n = 152). Ninety-three pairs of patients with similar characteristics were selected by PS matching. The urgent ERCP group had more ICU admissions (34.4% vs 21.5%, P = 0.05), shorter ICU stays (3 d vs 9 d, P < 0.001), fewer antibiotic use (6 d vs 9 d, P < 0.001), and shorter hospital stays (9 d vs 18.5 d, P < 0.001). There were no significant differences observed in adverse events, in-hospital mortality, recurrent cholangitis occurrence, 30-d readmission rate or 30-d mortality. CONCLUSION: Urgent one-stage ERCP provides the advantages of a shorter ICU stay, a shorter duration of antibiotic use, and a shorter hospital stay.

Biotransformation of Ginsenoside Rb1 to Ginsenoside Rd and 7 Rare Ginsenosides Using Irpex lacteus with HPLC-HRMS/MS Identification.

The biotransformation of ginsenosides using microorganisms represents a promising and ecofriendly approach for the production of rare ginsenosides. The present study reports on the biotransformation of ginsenoside Rb1 using the fungus Irpex lacteus, resulting in the production of ginsenoside Rd and seven rare ginsenosides with novel structures. Employing high-performance liquid chromatography coupled with high-resolution tandem mass spectrometry, the identities of the transformation products were rapidly determined. Two sets of isomers with molecular weights of 980.56 and 962.55 were discovered among the seven rare ginsenosides, which were generated through the isomerization of the olefin chain in the protopanaxadiol (PPD)-type ginsenoside skeleton. Each isomer exhibited characteristic fragment ions and neutral loss patterns in their tandem mass spectra, providing evidence of their unique structures. Time-course experiments demonstrated that the transformation reaction reached equilibrium after 14 days, with Rb1 initially generating Rd and compound 5, followed by the formation of other rare ginsenosides. The biotransformation process catalyzed by I. lacteus was found to involve not only the typical deglycosylation reaction at the C-20 position but also hydroxylation at the C-22 and C-23 positions, as well as hydrogenation, transfer, and cyclization of the double bond at the C-24(25) position. These enzymatic capabilities extend to the structural modification of other PPD-type ginsenosides such as Rc and Rd, revealing the potential of I. lacteus for the production of a wider range of rare ginsenosides. The transformation activities observed in I. lacteus are unprecedented among fungal biotransformations of ginsenosides. This study highlights the application of a medicinal fungi-based biotransformation strategy for the generation of rare ginsenosides with enhanced structural diversity, thereby expanding the variety of bioactive compounds derived from ginseng.