Cancer Cachexia in STK11/LKB1 -mutated NSCLC is Dependent on Tumor-secreted GDF15.

Cachexia is a wasting syndrome comprised of adipose, muscle, and weight loss observed in cancer patients. Tumor loss-of-function mutations in STK11/LKB1 , a regulator of the energy sensor AMP-activated protein kinase, induce cancer cachexia (CC) in preclinical models and are associated with cancer-related weight loss in NSCLC patients. Here we characterized the relevance of the NSCLC-associated cachexia factor growth differentiation factor 15 (GDF15) in several patient-derived and genetically engineered STK11/LKB1 -mutant NSCLC cachexia lines. Both tumor mRNA expression and serum concentrations of tumor-derived GDF15 were significantly elevated in multiple mice transplanted with patient-derived STK11/LKB1 -mutated NSCLC lines. GDF15 neutralizing antibody administered to mice transplanted with patient- or mouse-derived STK11/LKB1 -mutated NSCLC lines suppressed cachexia-associated adipose loss, muscle atrophy, and changes in body weight. The silencing of GDF15 in multiple human NSCLC lines was also sufficient to eliminate in vivo circulating GDF15 levels and abrogate cachexia induction, suggesting that tumor and not host tissues represent a key source of GDF15 production in these cancer models. Finally, reconstitution of wild-type STK11/LKB1 in a human STK11/LKB1 loss-of-function NSCLC line that normally induces cachexia in vivo correlated with the absence of tumor-secreted GDF15 and rescue from the cachexia phenotype. The current data provide evidence for tumor-secreted GDF15 as a conduit and a therapeutic target through which NSCLCs with STK11/LKB1 loss-of-function mutations promote cachexia-associated wasting.

The application of organoids in colorectal diseases.

Intestinal organoids are a three-dimensional cell culture model derived from colon or pluripotent stem cells. Intestinal organoids constructed in vitro strongly mimic the colon epithelium in cell composition, tissue architecture, and specific functions, replicating the colon epithelium in an in vitro culture environment. As an emerging biomedical technology, organoid technology has unique advantages over traditional two-dimensional culture in preserving parental gene expression and mutation, cell function, and biological characteristics. It has shown great potential in the research and treatment of colorectal diseases. Organoid technology has been widely applied in research on colorectal topics, including intestinal tumors, inflammatory bowel disease, infectious diarrhea, and intestinal injury regeneration. This review focuses on the application of organoid technology in colorectal diseases, including the basic principles and preparation methods of organoids, and explores the pathogenesis of and personalized treatment plans for various colorectal diseases to provide a valuable reference for organoid technology development and application.

Biomechanical analysis of fixation methods for bone flap repositioning after lateral orbitotomy approach: A finite element analysis.

OBJECTIVE: In ophthalmic surgery, different materials and fixation methods are employed for bone flap repositioning after lateral orbitotomy approach (LOA), yet there is no unified standard. This study aims to investigate the impact of different fixation strategies on orbital stability through Finite Element Analysis (FEA) simulations of the biomechanical environment for orbital rim fixation in LOA. METHODS: A Finite Element Model (FEM) was established and validated to simulate the mechanical responses under various loads in conventional lateral orbitotomy approach (CLOA) and deep lateral orbital decompression (DLOD) using single titanium plate, double titanium plates, and double absorbable plates fixation methods. The simulations were then validated against clinical cases. RESULTS: Under similar conditions, the maximum equivalent stress (MES) on titanium alloy fixations was greater than that on absorbable plate materials. Both under static and physiological conditions, all FEM groups ensured structural stability of the system, with material stresses remaining within safe ranges. Compared to CLOA, DLOD, which involves the removal of the lateral orbital wall, altered stress conduction, resulting in an increase of MES and maximum total deformation (MTD) by 1.96 and 2.62 times, respectively. Under a horizontal load of 50 N, the MES in FEM/DLOD exceeded the material's own strength, with an increase in MES and MTD by 3.18 and 6.64 times, respectively, compared to FEM/CLOA. Under a vertical force of 50 N, the MES sustained by each FEM was within safe limits. Bone flap rotation angles remained minimally varied across scenarios. During follow-up, the 12 patients validated in this study did not experience complications related to the internal fixation devices. CONCLUSION: Under static or physiological conditions, various fixation methods can effectively maintain stability at the orbitotomy site, and absorbable materials, with their smoother stress transmission properties, are more suited for application in CLOA. Among titanium plate fixations, single titanium plates can better withstand vertical stress, while double titanium plates are more capable of handling horizontal stress. Given the change in the orbital mechanical behavior due to DLOD, enhanced fixation strength should be considered for bone flap repositioning.

Effect of navigation endoscopy combined with three-dimensional printing technology in the treatment of orbital blowout fractures.

AIM: To explore the combined application of surgical navigation nasal endoscopy (NNE) and three-dimensional printing technology (3DPT) for the adjunctive treatment of orbital blowout fractures (OBF). METHODS: Retrospective analysis was conducted on the data of patients with OBF who underwent surgical treatment at the Affiliated Eye Hospital of Nanchang University between July 2012 and November 2022. The control group consisted of patients who received traditional surgical treatment (n=43), while the new surgical group (n=52) consisted of patients who received NNE with 3DPT. The difference in therapeutic effects between the two groups was evaluated by comparing the duration of the operation, best corrected visual acuity (BCVA), enophthalmos difference, recovery rate of eye movement disorder, recovery rate of diplopia, and incidence of postoperative complications. RESULTS: The study included 95 cases (95 eyes), with 63 men and 32 women. The patients' age ranged from 5 to 67y (35.21±15.75y). The new surgical group and the control group exhibited no statistically significant differences in the duration of the operation, BCVA and enophthalmos difference. The recovery rates of diplopia in the new surgical group were significantly higher than those in the control group at 1mo [OR=0.03, 95%CI (0.01-0.15), P<0.0000] and 3mo [OR=0.11, 95%CI (0.03-0.36), P<0.0000] post-operation. Additionally, the recovery rates of eye movement disorders at 1 and 3mo after surgery were OR=0.08, 95%CI (0.03-0.24), P<0.0000; and OR=0.01, 95%CI (0.00-0.18), P<0.0000. The incidence of postoperative complications was lower in the new surgical group compared to the control group [OR=4.86, 95%CI (0.95-24.78), P<0.05]. CONCLUSION: The combination of NNE and 3DPT can shorten the recovery time of diplopia and eye movement disorder in patients with OBF.

Initial implementation of surgical guide design utilizing digital medicine for lateral orbital decompression surgery.

This study aimed to assess the feasibility of utilizing a surgical guide, designed through digital medical technology, in lateral orbital decompression surgery. METHODS: In total, 18 patients with thyroid-associated ophthalmopathy (TAO), who underwent orbital balance decompression surgery at the Affiliated Eye Hospital of Nanchang University between September 2018 and August 2022, were included. Orbital CT scanning was performed on all patients with TAO, and Mimics 21.0 software was used to reconstruct a three-dimensional model of the orbit based on the CT data. The osteotomy guide plate for lateral orbital decompression surgery was designed using 3-matic 13.0 software, adhering to the criteria of surgical effectiveness and safety. The surgical positioning guide was designed using Geomagic Wrap 21.0. Once printed, the surgical guide was sterilized with low-temperature plasma and applied during surgery. Of the nine patients treated using a surgical navigation system, three cases experienced cerebrospinal fluid leakage complications during the procedure, and two exhibited inadequate bone removal along the lateral wall. In contrast, among the nine patients treated with surgical guides, no intraoperative cerebrospinal fluid leakage or evidence of insufficient lateral wall bone removal was observed, highlighting a statistically significant distinction between the two cohorts (p = 0.046). Postoperative improvements were notable in best-corrected visual acuity (BCVA) and exophthalmos for patients afflicted with extremely severe TAO. The surgical guide, designed with digital medical technology, has been shown to be an effective and secure auxiliary tool in lateral orbital decompression surgery. It not only aids in reducing the incidence of intraoperative complications, but also enhances the accuracy and safety of surgery. These improvements offer robust support for continued exploration in this field within clinical practice.

Diterpenoids from Euphorbia peplus possessing cytotoxic and anti-inflammatory activities.

Phytochemical investigation into the medium polar fraction of the ethanol extract of Euphorbia peplus led to the identification of 32 diterpenoids with five structural types. Compounds 1-5 and 7-11 are reported for the first time, while the configuration of 6,7-epoxy group of 6 was revised to be ß-oriented. Compounds 1-5 feature a rare structural variation of the double bond at Δ1 migrating to Δ1(10) in the tigliane-type diterpenoid family. Biologically, compound 21 was found to be the only one to show moderate cytotoxic activity, associated with the presence of a benzoyloxy residue at C-16. Besides, compounds 4, 8, 12, 13, 16, and 19 show significant inhibitory activities against NO production induced by LPS in RAW264.7 macrophage cells, with IC50 values within 2-5 µM. Structure-activity relationship (SAR) analysis revealed that the ingenane-type diterpenoids have the best anti-inflammatory activity, and the esterification at 3-OH or 5-OH is crucial. Further biological researches demonstrated that 13, the predominant metabolite in this plant, exerts anti-inflammatory effects by blocking the activation of NF-κB and MAPK signaling pathways.

Preparation of pH-responsive reversible wettable surfaces and application for oil-water separation.

With the continuous development of society, the discharge of oily wastewater in daily life and industry has gradually increased, causing considerable damage to the environment, and how to effectively treat oily wastewater is an urgent problem. In this paper, a simple method is proposed to prepare superhydrophobic stainless steel mesh with pH response. The relationship between the ratio of mixed thiols and the surface wettability was explored, as well as the morphology, chemical composition, and pH-responsive mechanism of the stainless steel mesh surface were analyzed, and the separation efficiency, recycling ability, and backwashing ability of the mesh were explored by oil-water separation experiments. It was found that when the molar fraction of 11-mercaptoundecanoic acid and 1-decanethiol in the mixed mercaptan was 2:3, the water contact angle of the surface at this point was 156.5 ± 1°, with pH response characteristics and good oil-water separation efficiency, backwashing and recycling capabilities.

Isovitexin prevents DSS-induced colitis through inhibiting inflammation and preserving intestinal barrier integrity through activating AhR.

Isovitexin (ISO) is a glycosylated flavonoid obtained from Asian rice that has been reported to have anti-inflammatory effect. However, the effects of ISO on colitis have not been reported. In the present study, we aimed to explore the protective effects of isovitexin on colitis using the dextran sodium sulfate (DSS)-induced model. In vitro, the protective mechanism was investigated in TNF-α-stimulated IEC cells. Inflammatory cytokines were measured by ELISA. The signaling pathways were measured by Western blot analysis. ISO attenuated DSS-induced colitis through reducing body weight loss and colonic histological changes. Also, the levels of TNF-α and IL-1ß induced by DSS were inhibited by ISO. The MPO activity induced by DSS was attenuated by ISO. In vitro, ISO inhibited IL-6 and IL-1ß production in TNF-α-stimulated cells. ISO increased the expression of tight junction proteins ZO-1 and occludin. Also, ISO inhibited TNF-α-induced NF-κB activation. In addition, ISO was found to increase the expression of aryl hydrocarbon receptor (AhR). And inhibition of AhR by its antagonist CH223191 could reverse these effects of ISO. ISO inhibited DSS-induced colitis in mice through suppressing inflammation and preserving intestinal barrier integrity through activating AhR. ISO may be useful as a potential therapeutic agent for colitis.

Tumor loss-of-function mutations in STK11/LKB1 induce cachexia.

Cancer cachexia (CC), a wasting syndrome of muscle and adipose tissue resulting in weight loss, is observed in 50% of patients with solid tumors. Management of CC is limited by the absence of biomarkers and knowledge of molecules that drive its phenotype. To identify such molecules, we injected 54 human non-small cell lung cancer (NSCLC) lines into immunodeficient mice, 17 of which produced an unambiguous phenotype of cachexia or non-cachexia. Whole-exome sequencing revealed that 8 of 10 cachexia lines, but none of the non-cachexia lines, possessed mutations in serine/threonine kinase 11 (STK11/LKB1), a regulator of nutrient sensor AMPK. Silencing of STK11/LKB1 in human NSCLC and murine colorectal carcinoma lines conferred a cachexia phenotype after cell transplantation into immunodeficient (human NSCLC) and immunocompetent (murine colorectal carcinoma) models. This host wasting was associated with an alteration in the immune cell repertoire of the tumor microenvironments that led to increases in local mRNA expression and serum levels of CC-associated cytokines. Mutational analysis of circulating tumor DNA from patients with NSCLC identified 89% concordance between STK11/LKB1 mutations and weight loss at cancer diagnosis. The current data provide evidence that tumor STK11/LKB1 loss of function is a driver of CC, simultaneously serving as a genetic biomarker for this wasting syndrome.

Cytokine-Mediated STAT3 Transcription Supports ATGL/CGI-58-Dependent Adipocyte Lipolysis in Cancer Cachexia.

Adipose tissue inflammation is observed in multiple metabolically-altered states including cancer-associated cachexia and obesity. Although cachexia is a syndrome of adipose loss and obesity is a disease of adipose excess, both pathologies demonstrate increases in circulating levels of IL-6 family cytokines, ß-adrenergic signaling, and adipocyte lipolysis. While ß-adrenergic-stimulated adipocyte lipolysis is well described, there is limited mechanistic insight into how cancer cachexia-associated inflammatory cytokines contribute to adipocyte lipolysis under pathologic conditions. Here, we set out to compare adipocyte lipolysis signaling by cancer cachexia-associated IL-6 family cytokines (IL-6 and LIF) to that of the ß-adrenergic agonist isoproterenol. Unlike isoproterenol, the IL-6 family of cytokines required JAK/STAT3-dependent transcriptional changes to induce adipocyte lipolysis. Furthermore, cachexia-associated cytokines that used STAT3 to induce lipolysis were primarily dependent on the lipase ATGL and its cofactor CGI-58 rather than lipases HSL and MAGL. Finally, administration of JAK but not ß-adrenergic inhibitors suppressed adipose STAT3 phosphorylation and associated adipose wasting in a murine model of cancer cachexia characterized by increased systemic IL-6 family cytokine levels. Combined, our results demonstrate how the IL-6 family of cytokines diverge from ß-adrenergic signals by employing JAK/STAT3-driven transcriptional changes to promote adipocyte ATGL/CGI-58-dependent lipolysis contributing to adipose wasting in cancer cachexia.

Effectiveness of a combined problem-based learning and flipped classroom teaching method in ophthalmic clinical skill training.

BACKGROUND: Previous studies have primarily implemented problem-based learning (PBL) or flipped classroom (FC) teaching models in different majors; however, research on the combined PBL-FC teaching method in clinical medicine is scarce. Therefore, we investigated the combined PBL-FC teaching method in teaching ocular trauma on students' competencies. METHOD: About 75 ophthalmology postgraduates were randomly divided into PBL-FC and traditional teaching groups. Students completed pre-and post-class theoretical examinations, skills evaluation, learning ability scales, and feedback questionnaires. RESULTS: Both groups showed significantly higher theoretical scores and improved learning ability. Feedback questionnaire scores of the PBL-FC group's postgraduates without clinical experience were significantly higher than the traditional group's for some items; there was no difference between groups in postgraduates with clinical experience. PBL-FC group's pre-class preparation time was significantly longer than the traditional group's, but the post-class review time was significantly shorter. PBL-FC group's post-class theoretical performance was significantly higher than the traditional group's. There was no statistical difference between the groups regarding skill operation. Among postgraduates without clinical experience, the PBL-FC group's skill operation performance was significantly higher than the traditional group's; for postgraduates with clinical experience, the traditional group's skill operation performance was significantly higher than the PBL-FC group's. CONCLUSIONS: PBL-FC teaching is better for students without clinical experience or knowledge of ophthalmic diseases. Meanwhile, traditional teaching is a good choice for students with clinical experience who need more relevant knowledge.

Concentration, Health Risk, and Hydrological Forcing of Heavy Metals in Surface Water Following Water-Sediment Regulation of the Xiaolangdi Dam in the Yellow River.

Water and sediment regulation aimed at aquatic ecosystems and preserving reservoir capacity to minimize the negative consequences of dams can fundamentally change the distribution of heavy metals (HMs) in the reservoir and downstream reaches. However, the effects of water and sediment regulation on variation in HMs are still poorly understood. In this study, the variations in concentration, contamination, human health risk, potential sources, and influencing factors of the metalloid As and HMs (Cr, Hg, Ni, Pb, and Zn) in surface water in the reservoir and the downstream reach of the Xiaolangdi Dam (XLD) following the operation of the water-sediment regulation scheme (WSRS) were determined. These results indicate that HM concentrations in the two post-WSRS seasons were much lower than the water quality standards, but were significantly increased over time due to the trapping effects of the XLD (p < 0.05, except for Zn). However, As concentration in the reservoir was significantly lower than that observed in downstream reaches, likely due to anthropogenic input from agricultural activities. Meanwhile, HM concentrations varied with distance to the dam, which displayed a distinct accumulation closer to the dam in the post-WSRS II season. The contamination of HMs, the carcinogenic risk of exposure to As, and the noncarcinogenic risks associated with exposure to Hg, Ni, Pb, and Zn via the direct ingestion pathway of drinking water were all within acceptable levels following the WSRS, but increased over time. The carcinogenic risk of Cr in the post-WSRS II season was at an unacceptably high level, particularly at sites near the dam. Hydrological characteristics (water level and flow rate) were the dominant factors in determining the distribution of HMs. These results can provide new insight for a better understanding of the variations in HMs following the water and sediment regulation practices, and guide future management in regulating the trapping effects of dams.

Biological activity of a vascular endothelial cell-hydroxyapatite orbital implant complex: An experimental study.

The reduction in postoperative complications is a considerable concern after orbital reparation and reconstruction. Selecting the appropriate scaffold materials to improve the survival rates of the seeded cells is a challenge in tissue engineering. The aim of the present study was to evaluate the biological activity of a vascular endothelial cell-hydroxyapatite orbital complex, which was constructed with tissue engineering and used as an implant after enucleation of the eyeNew Zealand white rabbits were randomly divided into two groups that underwent hydroxyapatite orbital implant surgery in the right eye. The primary orbital microvascular endothelial cells were collected from the microvascular tissue and subsequently cultured. Then, hydroxyapatite ocular implants were cultured with vascular endothelial cells in the endothelial cell (EC) group, and implants were cultured without vascular endothelial cells in the blank group. Characterization of the cells was performed with immunofluorescence staining and a Transwell migration and cell tube formation assay. The levels of interleukin-8 (IL-8) and vascular endothelial growth factor (VEGF) in the rabbit conjunctiva were measured with an ELISA. The results showed that the levels of IL-8 were decreased in the EC group and increased in the blank group. The levels of VEGF were increased in the EC group when compared to the blank group with statistical significance. The average depth of the fibrovascular tissue was obviously thicker in the EC group compared with that found in the blank group. These findings suggest that the vascular endothelial cell-hydroxyapatite orbital implant complex may be an effective strategy with which to accelerate vascularization and reduce complications of infection with satisfactory biological activity.

Long non-coding RNA FOXP4-AS1 facilitates the biological functions of hepatocellular carcinoma cells via downregulating ZC3H12D by mediating H3K27me3 through recruitment of EZH2.

BACKGROUND: Some studies have reported the effect of long non-coding RNA forkhead box P4 antisense RNA 1 (lncRNA FOXP4-AS1) on hepatocellular carcinoma (HCC). Here, we aimed to discuss the effects of FOXP4-AS1/enhancer of zeste homolog 2 (EZH2)/trimethylation of lysine 27 on histone H3 (H3K27me3)/zinc finger CCCH-type containing 12D (ZC3H12D) axis on HCC. METHODS: The expression of FOXP4-AS1, EZH2, and ZC3H12D, and abundance of H3K27me3 in HCC tissues and cells were tested. The relationship between FOXP4-AS1 expression and prognosis of HCC patients was analyzed. The biological functions of HCC cells were detected via loss- and gain-of-function assays. The tumor weight and volume in vivo were tested. The interaction between FOXP4-AS1 and EZH2 as well as that between EZH2 and H3K27me3 was verified. RESULTS: FOXP4-AS1 and EZH2 expression and H3K27me3 abundance were enhanced while ZC3H12D expression was depressed in HCC tissues and cells. Knockdown of FOXP4-AS1 suppressed biological functions of HCC cells as well as the weight and volume of HCC transplanted tumor. Depleting ZC3H12D reversed the effect of downregulated FOXP4-AS1 on HCC cells. FOXP4-AS1 suppressed ZC3H12D expression via mediating H3K27me3 by recruitment of EZH2. CONCLUSION: The key findings of the present study demonstrate that FOXP4-AS1 suppresses ZC3H12D expression via mediating H3K27me3 by recruitment of EZH2, thus promoting the progression of HCC.

LIFR-α-dependent adipocyte signaling in obesity limits adipose expansion contributing to fatty liver disease.

The role of chronic adipose inflammation in diet-induced obesity (DIO) and its sequelae including fatty liver disease remains unclear. Leukemia inhibitory factor (LIF) induces JAK-dependent adipocyte lipolysis and altered adipo/cytokine expression, suppressing in vivo adipose expansion in normal and obese mouse models. To characterize LIF receptor (LIFR-α)-dependent cytokine signaling in DIO, we created an adipocyte-specific LIFR knockout mouse model (Adipoq-Cre;LIFR fl/fl ). Differentiated adipocytes derived from this model blocked LIF-induced triacylglycerol lipolysis. Adipoq-Cre;LIFR fl/fl mice on a high-fat diet (HFD) displayed reduced adipose STAT3 activation, 50% expansion in adipose, 20% body weight increase, and a 75% reduction in total hepatic triacylglycerides compared with controls. To demonstrate that LIFR-α signals adipocytes through STAT3, we also created an Adipoq-Cre;STAT3 fl/fl model that showed similar findings when fed a HFD as Adipoq-Cre;LIFR fl/fl mice. These findings establish the importance of obesity-associated LIFR-α/JAK/STAT3 inflammatory signaling in adipocytes, blocking further adipose expansion in DIO contributing to ectopic liver triacylglyceride accumulation.

Biological role of postoperative low level laser therapy in preventing hydroxyapatite orbital implantation exposure: A case report.

Conjunctival sac stenosis is the contraction of the conjunctival sac as a result of trauma or disease. The aim of the present study was to observe the clinical effects of low-level laser therapy (LLLT) combined with hydroxyapatite (HA) orbital implantation as a treatment strategy for conjunctival sac stenosis. A total of 10 patients with conjunctival sac stenosis were treated with scleral graft transplantation in conjunction with HA implantation and postoperative LLLT. In addition, a rabbit model was used to investigate the biological mechanism underlying the effects of LLLT with the aim of preventing and treating orbital implantation exposure. The right eyeball was removed, orbital implantation performed and LLLT applied to experimental groups. 99mTc-Methyl diphosphonate scanning methods were performed at different timepoints to compare the average radioactivity count of the region of interest between surgical (right) and control (left) eyes (R/L). Histopathological examination was performed 8 weeks post-surgery, followed by analysis of fiber vascularization. Following LLLT, moderate conjunctival wounds were completely healed within 2 weeks and severe stenosis wounds healed within 3 weeks. Following prosthesis implantation in the rabbit model, a significantly elevated R/L ratio was observed after 4 weeks, whereas no significant difference was observed compared with the control group at 6 and 8 weeks postoperatively. Histopathological examination revealed that all implants were fibrotic. Overall, the present study demonstrated that LLLT promoted the survival of conjunctival grafts, stimulated conjunctival incision healing and promoted early vascularization of HA implants. Clinical trial registration no: ChiCTR-DDT-12002660 (www.chictr.org/cn/).

Bioactive sesquiterpenoids from the flower buds of Tussilago farfara.

Eleven new compounds including five bisabolane (1-5) and three oplopane (6-8) sesquiterpenoids, a pair of benzopyran enantiomers (9 & 10) and a benzofuran derivative (11), along with six known sesquiterpenoid co-metabolites (12-17), have been obtained from the flower buds of Tussilago farfara. Their structures were elucidated by comprehensive spectroscopic analyses and comparison with structurally related known analogues. The absolute configurations of all the compounds except 11 were unequivocally assigned by various techniques, including Mosher's method and time-dependent density functional theory (TD-DFT) based calculations of 13C NMR and electronic circular dichroism (ECD) data. The C-8 absolute configuration on the sidechain of this group of bisabolane sesquiterpenoids was assigned for the first time. Our bioassays have established that compounds 3, 4, 13 and 14 showed significant α-glucosidase inhibitory activities, while 6, 8 and 14 displayed moderate antiproliferative effects against two human tumor cell lines A549 and MDA-MB-231. Further flow cytometric analysis revealed that 14 effectively induced cell apoptosis and arrested cell cycle at the S/G2 phases in A549 cells, in a dose-dependent manner.

Cytotoxic ergostane-type steroids from Ganoderma lingzhi.

Two new ergostane-type steroids (1 and 2) have been isolated from the fruiting body of a medicinal macro fungus Ganoderma lingzhi. The structures including the absolute configurations of them were elucidated by a combination of different spectroscopic analyses especially 13C NMR and ECD calculations. Compound 2 features an unusual 1,2-dioxolane moiety. Our bioassays revealed that the two steroids showed remarkable cytotoxicity against human A549 (lung) and MCF-7 (breast) tumor cell lines, with IC50 values ranging from 5.15 to 8.57 µg/mL.

Efficient synthesis of γ-glutamyl compounds by co-expression of γ-glutamylmethylamide synthetase and polyphosphate kinase in engineered Escherichia coli.

γ-Glutamyl compounds have unveiled their importance as active substances or precursors of pharmaceuticals. In this research, an approach for enzymatic synthesis of γ-glutamyl compounds was developed using γ-glutamylmethylamide synthetase (GMAS) from Methylovorus mays and polyphosphate kinase (PPK) from Corynebacterium glutamicum. GMAS and PPK were co-recombined in pETDuet-1 plasmid and co-expressed in E. coli BL21 (DE3), and the enzymatic properties of GMAS and PPK were investigated, respectively. Under the catalysis of the co-expression system, L-theanine was synthesized with 89.8% conversion when the substrate molar ratio of sodium glutamate and ethylamine (1:1.4) and only 2 mM ATP were used. A total of 14 γ-glutamyl compounds were synthesized by this one-pot method and purified by cation exchange resin and isoelectric point crystallization with a yield range from 22.3 to 72.7%. This study provided an efficient approach for the synthesis of γ-glutamyl compounds by GMAS and PPK co-expression system.

Osthole resensitizes CD133+ hepatocellular carcinoma cells to cisplatin treatment via PTEN/AKT pathway.

The population of CD133 positive cancer cells has been reported to be responsible for drug resistance of hepatocellular carcinoma (HCC). However, the potential molecular mechanism by which CD133+ HCC cells develop drug resistance is still unclear. In this study, we found that CD133+ HepG2 and Huh7 cells were resistant to cisplatin treatment, compared to the CD133- HepG2 and Huh7 cells. However, treatment with osthole, a natural coumarin isolated from umbelliferae plant monomers, was found to resensitize CD133+ HepG2 and Huh7 cells to cisplatin treatment. In the mechanism research, we found that treatment with osthole increased the expression of PTEN. As a result, osthole inhibited the phosphorylation of AKT and Bad to decrease the amount of free Bcl-2 in CD133+ HepG2 and Huh7 cells. Finally, cisplatin-induced mitochondrial apoptosis was expanded. In conclusion, combination treatment with osthole can resensitize CD133+ HCC cells to cisplatin treatment via the PTEN/AKT pathway.