Single-site iron-anchored amyloid hydrogels as catalytic platforms for alcohol detoxification.

Constructing effective antidotes to reduce global health impacts induced by alcohol prevalence is a challenging topic. Despite the positive effects observed with intravenous applications of natural enzyme complexes, their insufficient activities and complicated usage often result in the accumulation of toxic acetaldehyde, which raises important clinical concerns, highlighting the pressing need for stable oral strategies. Here we present an effective solution for alcohol detoxification by employing a biomimetic-nanozyme amyloid hydrogel as an orally administered catalytic platform. We exploit amyloid fibrils derived from ß-lactoglobulin, a readily accessible milk protein that is rich in coordinable nitrogen atoms, as a nanocarrier to stabilize atomically dispersed iron (ferrous-dominated). By emulating the coordination structure of the horseradish peroxidase enzyme, the single-site iron nanozyme demonstrates the capability to selectively catalyse alcohol oxidation into acetic acid, as opposed to the more toxic acetaldehyde. Administering the gelatinous nanozyme to mice suffering from alcohol intoxication significantly reduced their blood-alcohol levels (decreased by 55.8% 300 min post-alcohol intake) without causing additional acetaldehyde build-up. Our hydrogel further demonstrates a protective effect on the liver, while simultaneously mitigating intestinal damage and dysbiosis associated with chronic alcohol consumption, introducing a promising strategy in effective alcohol detoxification.

An Inulin-Type Fructan CP-A from Codonopsis pilosula Alleviated 5-Fluorouracil-Induced Intestinal Mucositis via the ERK/MLCK/MLC2 Pathway and Regulation of Gut Microbiota.

Intestinal mucositis (IM) is a common adverse effect of chemotherapy, limiting its clinical application. Codonopsis pilosula-derived CP-A (an inulin-type fructan) is an edible Chinese medicine with anti-inflammatory and gastrointestinal protective effects, which may be useful for treating IM. Here, we explored CP-A's role in ameliorating IM induced by 5-fluorouracil (5-FU) and investigated the underlying mechanism using in vitro experiments and rat models. Western blotting, immunohistochemistry (IHC), and real-time PCR (RT-PCR) analyses were used to assess protein expression related to the extracellular-regulated protein kinases (ERK)/myosin light chain kinase (MLCK)/myosin light chain 2 (MLC2) signaling pathway and tight junction proteins. Inflammatory factors were quantified using enzyme-linked immunosorbent assays (ELISAs), and 16S rRNA amplicon sequencing was employed for cecum content analysis. The results indicated that CP-A restored body weight and food intake and reversed histopathological changes in IM rats. Further, abnormal MLCK activation induced by 5-FU was attenuated by CP-A via the ERK/MLCK/MLC2 pathway. CP-A treatment improved tight junction protein levels and reduced inflammatory factor expression. Moreover, CP-A intervention regulated the intestinal microbiota community structure, increasing the abundance of Lactobacillus and decreasing the abundance of Shigella. In conclusion, CP-A mitigates 5-FU-induced IM by inhibiting the ERK/MLCK/MLC2 pathway, reducing the expression of inflammatory factors, improving the intestinal mucosal barrier, and regulating the intestinal microbial community. This study highlights CP-A's therapeutic potential in IM treatment and provides insights for future research.

An inulin-type fructan CP-A from Codonopsis pilosula attenuates experimental colitis in mice by promoting autophagy-mediated inactivation of NLRP3 inflammasome.

Inulin-type fructan CP-A, a predominant polysaccharide in Codonopsis pilosula, demonstrates regulatory effects on immune activity and anti-inflammation. The efficacy of CP-A in treating ulcerative colitis (UC) is, however, not well-established. This study employed an in vitro lipopolysaccharide (LPS)-induced colonic epithelial cell model (NCM460) and an in vivo dextran sulfate sodium (DSS)-induced colitis mouse model to explore CP-A's protective effects against experimental colitis and its underlying mechanisms. We monitored the clinical symptoms in mice using various parameters: body weight, disease activity index (DAI), colon length, spleen weight, and histopathological scores. Additionally, molecular markers were assessed through enzyme-linked immunosorbent assay (ELISA), quantitative real-time polymerase chain reaction (qRT-PCR), immunofluorescence (IF), immunohistochemistry (IHC), and Western blotting assays. Results showed that CP-A significantly reduced reactive oxygen species (ROS), tumor necrosis factor-alpha (TNF-α), and interleukins (IL-6, IL-1ß, IL-18) in LPS-induced cells while increasing IL-4 and IL-10 levels and enhancing the expression of Claudin-1, ZO-1, and occludin proteins in NCM460 cells. Correspondingly, in vivo findings revealed that CP-A administration markedly improved DAI, reduced colon shortening, and decreased the production of myeloperoxidase (MPO), malondialdehyde (MDA), ROS, IL-1ß, IL-18, and NOD-like receptor protein 3 (NLRP3) inflammasome-associated genes/proteins in UC mice. CP-A treatment also elevated glutathione (GSH) and superoxide dismutase (SOD) levels, stimulated autophagy (LC3B, P62, Beclin-1, and ATG5), and reinforced Claudin-1 and ZO-1 expression, thereby aiding in intestinal epithelial barrier repair in colitis mice. Notably, the inhibition of autophagy via chloroquine (CQ) diminished CP-A's protective impact against colitis in vivo. These findings elucidate that CP-A's therapeutic effect on experimental colitis possibly involves mitigating intestinal inflammation through autophagy-mediated NLRP3 inflammasome inactivation. Consequently, inulin-type fructan CP-A emerges as a promising drug candidate for UC treatment.

Designed modular protein hydrogels for biofabrication.

Designing proteins that fold and assemble over different length scales provides a way to tailor the mechanical properties and biological performance of hydrogels. In this study, we designed modular proteins that self-assemble into fibrillar networks and, as a result, form hydrogel materials with novel properties. We incorporated distinct functionalities by connecting separate self-assembling (A block) and cell-binding (B block) domains into single macromolecules. The number of self-assembling domains affects the rigidity of the fibers and the final storage modulus G' of the materials. The mechanical properties of the hydrogels could be tuned over a broad range (G' = 0.1 - 10 kPa), making them suitable for the cultivation and differentiation of multiple cell types, including cortical neurons and human mesenchymal stem cells. Moreover, we confirmed the bioavailability of cell attachment domains in the hydrogels that can be further tailored for specific cell types or other biological applications. Finally, we demonstrate the versatility of the designed proteins for application in biofabrication as 3D scaffolds that support cell growth and guide their function. STATEMENT OF SIGNIFICANCE: Designed proteins that enable the decoupling of biophysical and biochemical properties within the final material could enable modular biomaterial engineering. In this context, we present a designed modular protein platform that integrates self-assembling domains (A blocks) and cell-binding domains (B blocks) within a single biopolymer. The linking of assembly domains and cell-binding domains this way provided independent tuning of mechanical properties and inclusion of biofunctional domains. We demonstrate the use of this platform for biofabrication, including neural cell culture and 3D printing of scaffolds for mesenchymal stem cell culture and differentiation. Overall, this work highlights how informed design of biopolymer sequences can enable the modular design of protein-based hydrogels with independently tunable biophysical and biochemical properties.

An inulin-type fructan CP-A from Codonopsis pilosula alleviates TNBS-induced ulcerative colitis based on serum-untargeted metabolomics.

Ulcerative colitis (UC) is an inflammatory disease with abdominal pain, diarrhea, and bloody stool as the main symptoms. Several studies have confirmed that polysaccharides are effective against UC. It is commonly accepted that the traditional benefits of Radix Codonopsis can be attributed to its polysaccharide contents, and inulin-type fructan CP-A is the main active monomer in the polysaccharide components. Herein, we established a 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced UC rat model and lipopolysaccharide (LPS)-induced colonic epithelial cell model (NCM460) to investigate the effect of CP-A on UC. Untargeted metabolomics studies were conducted to identify differential metabolites using ultra-high performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry (UHPLC-Q-TOF/MS) and enrich metabolic pathways in rat serum. The in vivo assays demonstrated that CP-A reduces colonic macroscopic injury, disease activity index (DAI), histopathological score, interleukin (IL)-8, and tumor necrosis factor-α (TNF-α) levels, as well as the expression of intercellular adhesion molecules. On the other hand, CP-A increases IL-10 and transforming growth factor-ß (TGF-ß) levels. The in vitro experiments indicated that CP-A treatment could reduce nitric oxide (NO) and IL-1ß after LPS stimulation. The metabolomics results suggested that CP-A therapy for UC may be related to the mammalian target of rapamycin (mTOR) signaling pathway. The in vitro and in vivo validation of the pathway showed similar results, indicating that CP-A alleviates UC by preventing the activation of mTOR/p70S6K signaling pathway. These findings offer a fresh approach to treating UC and a theoretical foundation for the future advancement of CP-A.NEW & NOTEWORTHY We report that an inulin-type fructan from Codonopsis pilosula CP-A exhibits a therapeutic effect on experimental colitis. Its mechanism may be to alleviate intestinal inflammation by preventing the activation of mammalian target of rapamycin (mTOR)/p70S6K signaling pathway. These findings offer a fresh approach to treating ulcerative colitis (UC) and a theoretical foundation for the future advancement of CP-A.

Comparison of a novel tablet formulation of tacrolimus and conventional capsule formulation in de novo kidney transplant recipients: a systematic review and meta-analysis.

Background: The work aimed to compare the pharmacokinetic (PK) profiles and other outcomes reported in observational studies in de novo kidney transplant recipients (KTRs) receiving novel once-daily extended-release tablet tacrolimus (LCPT; LCP-tacrolimus; Envarsus XR) or receiving standard-of-care capsule tacrolimus (PR-Tac; prolonged-release tacrolimus; Advagraf/IR-Tac; immediate-release tacrolimus; Prograf). Methods: A systematic review was conducted for all randomized controlled trials (RCTs) and cohort studies investigating the outcomes in KTRs receiving LCPT or PR-Tac/IR-Tac. We systematically searched PubMed, Web of Science, and EMBASE, with no language restriction. The registered trials and references listed in relevant studies were also searched. Data were extracted for the PK profile, tacrolimus trough level (TTL), and changes in the estimated glomerular filtration rate (eGFR) and serum creatinine (Scr), biopsy-proven acute rejection (BPAR) rate, delayed graft function (DGF) rate, post-transplant diabetes mellitus (PTDM) rate, tremor rate (TR), death rate (DR), and rate of infection by cytomegalovirus (CMV). This study was registered with PROSPERO (registration number: CRD42023403787). Results: A total of seven eligible articles including 1,428 patients with 712 in the LCPT group versus 716 in the PR-Tac/IR-Tac group were included in this study for evidence synthesis. The baseline characteristics of the LCPT, PR-Tac, and IR-Tac groups were similar. The pooled analysis showed a higher PK profile in the LCPT group, and this result was consistent with those of all the included studies. In addition, no significant difference was observed for other outcomes. Conclusion: Considering heterogeneity between studies and potential bias, care providers should select agents based on patient-specific factors and their clinical experience for the immunosuppressive treatment of de novo KTRs.

Establishment and application of three predictive models of anastomotic leakage after rectal cancer sphincter-preserving surgery.

BACKGROUND: Anastomotic leakage (AL) occurs frequently after sphincter-preserving surgery for rectal cancer and has a significant mortality rate. There are many factors that influence the incidence of AL, and each patient's unique circumstances add to this diversity. The early identification and prediction of AL after sphincter-preserving surgery are of great significance for the application of clinically targeted preventive measures. Developing an AL predictive model coincides with the aim of personalised healthcare, enhances clinical management techniques, and advances the medical industry along a more precise and intelligent path. AIM: To develop nomogram, decision tree, and random forest prediction models for AL following sphincter-preserving surgery for rectal cancer and to evaluate the predictive efficacy of the three models. METHODS: The clinical information of 497 patients with rectal cancer who underwent sphincter-preserving surgery at Jincheng People's Hospital of Shanxi Province between January 2017 and September 2022 was analyzed in this study. Patients were divided into two groups: AL and no AL. Using univariate and multivariate analyses, we identified factors influencing postoperative AL. These factors were used to establish nomogram, decision tree, and random forest models. The sensitivity, specificity, recall, accuracy, and area under the receiver operating characteristic curve (AUC) were compared between the three models. RESULTS: AL occurred in 10.26% of the 497 patients with rectal cancer. The nomogram model had an AUC of 0.922, sensitivity of 0.745, specificity of 0.966, accuracy of 0.936, recall of 0.987, and accuracy of 0.946. The above indices in the decision tree model were 0.919, 0.833, 0.862, 0.951, 0.994, and 0.955, respectively and in the random forest model were 1.000, 1.000, 1.000, 0.951, 0.994, and 0.955, respectively. The DeLong test revealed that the AUC value of the decision-tree model was lower than that of the random forest model (P < 0.05). CONCLUSION: The random forest model may be used to identify patients at high risk of AL after sphincter-preserving surgery for rectal cancer owing to its strong predictive effect and stability.

Fast Probing Amyloid Polymorphism via Nanopore Translocation.

Neurodegenerative diseases are characterized by the presence of cross-ß-sheet amyloid fibrils and a rich mesoscopic polymorphism, requiring noninvasive detection with high fidelity. Here, we introduce a methodology that can probe via a sensitive synthetic nanopore the complex polymorphism of amyloid fibrils by an automated and fast screening protocol. Statistically analyzing the translocation events on two model amyloid systems derived from ß-lactoglobulin and lysozyme allows extracting the cross-sectional configuration of hydrated amyloid fibrils from current block amplitude and correlating dwell time with fibril length. These findings are consistent with the amyloid polymorphs observed in solution by atomic force microscopy. Furthermore, the ionic current signal of a single translocation event can reveal abnormally aggregated conformations of amyloid fibrils without potential artifacts associated with microscopy methods. This study introduces an effective approach to physically discriminating and separating amyloid and may serve in the rapid diagnosis of early aggregating pathological amyloidosis.

Highly Adhesive Amyloid-Polyphenol Hydrogels for Cell Scaffolding.

Rationally designing microstructures of soft hydrogels for specific biological functionalization is a challenge in tissue engineering applications. A novel and affordable soft hydrogel scaffold is constructed here by incorporating polyphenol modules with lysozyme amyloid fibrils (Lys AFs) via non-covalent self-assembly. Embedded polyphenols not only trigger hydrogel formation but also determine gel behavior by regulating the polyphenol gallol density and complex ratio. The feasibility of using a polyphenol-Lys AF hydrogel as a biocompatible cell scaffold, which is conducive to cell proliferation and spreading, is also shown. Notably, introducing polyphenols imparts the corresponding hydrogels a superior cell bioadhesive efficiency without further biofunctional decoration and thus may be successfully employed in both healthy and cancer cell lines. Confocal laser scanning microscopy also reveals that the highly expressed integrin-mediated focal adhesions form due to stimulation of the polyphenol-AF composite hydrogel, direct cell adhesion, proliferation, and spreading. Overall, this work constitutes a significant step forward in creating highly adhesive tissue culture platforms for in vitro culture of different cell types and may greatly expand prospects for future biomaterial design and development.

Neurotoxic amyloidogenic peptides in the proteome of SARS-COV2: potential implications for neurological symptoms in COVID-19.

COVID-19 is primarily known as a respiratory disease caused by SARS-CoV-2. However, neurological symptoms such as memory loss, sensory confusion, severe headaches, and even stroke are reported in up to 30% of cases and can persist even after the infection is over (long COVID). These neurological symptoms are thought to be produced by the virus infecting the central nervous system, however we don't understand the molecular mechanisms triggering them. The neurological effects of COVID-19 share similarities to neurodegenerative diseases in which the presence of cytotoxic aggregated amyloid protein or peptides is a common feature. Following the hypothesis that some neurological symptoms of COVID-19 may also follow an amyloid etiology we identified two peptides from the SARS-CoV-2 proteome that self-assemble into amyloid assemblies. Furthermore, these amyloids were shown to be highly toxic to neuronal cells. We suggest that cytotoxic aggregates of SARS-CoV-2 proteins may trigger neurological symptoms in COVID-19.

Oat Plant Amyloids for Sustainable Functional Materials.

Amyloid functional materials from amyloid fibril building blocks, produced in vitro from amyloidogenic natural proteins or synthetic peptides, show diverse functionalities ranging from environmental science and biomedicine, to nanotechnology and biomaterials. However, sustainable and affordable sources of amyloidogenic proteins remain the bottleneck for large-scale applications, and to date, interest remains essentially limited to fundamental studies. Plant-derived proteins would be an ideal source due to their natural abundance and low environmental impact. Hereby oat globulin, the primary protein of oat plant (Avena sativa), is utilized to yield high-quality amyloid fibrils and functional materials based thereof. These fibrils show a rich multistranded ribbon-like polymorphism and a fibrillization process with both irreversible and reversible pathways. The authors furthermore fabricate oat-amyloid aerogels, films, and membranes for possible use in water purification, sensors, and patterned electrodes. The sustainability footprint of oat-amyloids against other protein sources is demonstrated, anticipating an environmentally-efficient platform for advanced materials and technologies.

Zanthoxylum bungeanum Seed Oil Attenuates LPS-Induced BEAS-2B Cell Activation and Inflammation by Inhibiting the TLR4/MyD88/NF-κB Signaling Pathway.

BACKGROUND: Zanthoxylum bungeanum seed oil (ZBSO) is a natural essential oil derived from the seeds of the Chinese medicinal plant Zanthoxylum bungeanum, which has been investigated for antitumor and anti-inflammatory effects. However, little is known regarding the effects of ZBSO in chronic obstructive pulmonary disease (COPD). METHODS: In this study, lung epithelial cells (BEAS-2B) were induced by lipopolysaccharide (LPS) to establish an in vitro model of COPD, and cytotoxicity was detected by a cell counting kit 8 (CCK-8) assay. Griess test, enzyme-linked immunosorbent assay (ELISA), reverse transcriptase quantitative polymerase chain reaction (RT-qPCR), western blot, immunofluorescence, and molecular docking analyses were used to investigate the effects of ZBSO and its potential mechanisms. RESULTS: The results showed that LPS promoted the expression of nitric oxide (NO), reactive oxygen species (ROS), malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), matrix metalloproteinase-2 (MMP-2), MMP-9, cyclooxygenase-2 (COX-2), and prostaglandin E2 (PGE2), suggesting that LPS can induce inflammation and oxidative stress in BEAS-2B cells. ZBSO inhibits the LPS-induced expression of inflammatory mediators and proinflammatory cytokines in BEAS-2B cells. The molecular docking results indicated that active components in ZBSO could successfully dock with toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), and p65. Immunofluorescence and western blot analyses further demonstrated that ZBSO repressed protein expression associated with the TLR4/MyD88/nuclear factor-κB (NF-κB) signaling pathway. CONCLUSIONS: ZBSO reduced the inflammatory response and oxidative stress induced by LPS by inhibiting the TLR4/MyD88/NF-κB signaling pathway, thereby suppressing COPD. ZBSO may represent a promising therapeutic candidate for COPD treatment.

Brusatol inhibits laryngeal cancer cell proliferation and metastasis via abrogating JAK2/STAT3 signaling mediated epithelial-mesenchymal transition.

AIMS: This study aimed at investigating the role of Brusatol (BR) on human laryngeal squamous carcinoma cell (Hep-2) to study its underlying mechanism through in vitro and in vivo approaches. MATERIALS AND METHOD: In the present research, we employed various cell-based assays, such as cell proliferation, apoptosis, cell cycle assessment, migration and invasion assays were used to examine the anti-tumor effect of BR on Hep-2 cells. Immunohistochemistry (IHC), qRT-PCR and Western blotting were performed to study the underlying molecular mechanisms. To validate our in vitro findings we used a subcutaneous tumor-bearing model of Balb/c mice with Hep-2 cells of laryngeal carcinoma (LC) to study the inhibitory effect of BR on Hep-2 cells in vivo. KEY FINDINGS: The results indicated that BR markedly inhibited the viability, migration and invasion capacity of Hep-2 cells, with no significant toxic effect on normal Human bronchial epithelial cell line (BEAS-2B). Also, BR induced cellular apoptosis by blocking the cells in S phase to suppress cell proliferation. Immunohistochemistry results revealed that BR inhibited the protein expression levels of epithelial-mesenchymal transition (EMT)-related markers. Mechanistically, western blotting results exhibited that BR could suppress the protein expression of both JAK2/STAT3 and their phosphorylation levels. Our in vivo experiments further validated the anti-tumor effect of BR on Hep-2 cells in vitro, where BR suppressed the growth of xenograft laryngeal tumor without apparent toxicity. SIGNIFICANCE: The present study highlights the anti-LC effect of BR by possibly abrogating JAK2/STAT3 signaling mediated EMT process. BR may be a promising therapeutic candidate for the treatment of LC.

Rootstock-Scion Interaction Affects Cadmium Accumulation and Tolerance of Malus.

To understand the roles of Malus rootstock, scion, and their interaction in Cd accumulation and tolerance, four scion/rootstock combinations consisting of the apple cultivars "Hanfu" (HF) and "Fuji" (FJ) grafted onto M. baccata (Mb) or M. micromalus "qingzhoulinqin" (Mm) rootstocks differing in relative Cd tolerance were exposed either to 0 µM or 50 µM CdCl2 for 18 d. Cd accumulation and tolerance in grafted Malus plants varied within rootstock, scion, and rootstock-scion interaction. Cd-induced decreases in photosynthesis, photosynthetic pigment level, and biomass were lower for HF grafted onto Mb than those for HF grafted onto Mm. Reductions in growth and photosynthetic rate were always the lowest for HF/Mb. Cd concentration, bioconcentration factor (BCF), and translocation factor (Tf ) were always comparatively higher in HF and FJ grafted onto rootstock Mm than in HF and FJ grafted on Mb, respectively. When HF and FJ were grafted onto the same rootstock, the root Cd concentrations were always higher in HF than FJ, whereas the shoot Cd concentrations displayed the opposite trend. The shoot Cd concentrations and Tf were lower for HF/Mb than the other scion/rootstock combinations. Rootstock, scion, and rootstock-scion interaction also affected subcellular Cd distribution. Immobilization of Cd in the root cell walls may be a primary Cd mobility and toxicity reduction strategy in Malus. The rootstock and scion also had statistically significant influences on ROS level and antioxidant activity. Cd induced more severe oxidative stress in HF and FJ grafted onto Mm than it did in HF and FJ grafted onto Mb. Compared with FJ, HF had lower foliar O2 -, root H2O2, and root and leaf MDA levels, but higher ROS-scavenging capacity. The rootstock, scion, and rootstock-scion interaction affected the mRNA transcript levels of several genes involved in Cd uptake, transport, and detoxification including HA7, FRO2-like, NRAMP1, NRAMP3, HMA4, MT2, NAS1, and ABCC1. Hence, the responses of grafted Malus plants to Cd toxicity vary with rootstock, scion, and rootstock-scion interaction.

Fiber-Tip Polymer Microcantilever for Fast and Highly Sensitive Hydrogen Measurement.

Hydrogen as an antioxidant gas has been widely used in the medical and biological fields for preventing cancer or treating inflammation. However, controlling the hydrogen concentration is crucial for practical use due to its explosive property when its volume concentration in air reaches the explosive limit (4%). In this work, a polymer-based microcantilever (µ-cantilever) hydrogen sensor located at the end of a fiber tip is proposed to detect the hydrogen concentration in medical and biological applications. The proposed sensor was developed using femtosecond laser-induced two-photon polymerization (TPP) to print the polymer µ-cantilever and magnetron sputtering to coat a palladium (Pd) film on the upper surface of the µ-cantilever. Such a device exhibits a high sensitivity, roughly -2 nm %-1 when the hydrogen concentration rises from 0% to 4.5% (v/v) and a short response time, around 13.5 s at 4% (v/v), making it suitable for medical and environmental applications. In addition to providing an ultracompact optical solution for fast and highly sensitive hydrogen measurement, the polymer µ-cantilever fiber sensor can be used for diverse medical and biological sensing applications by replacing Pd with other functional materials.

Exogenous melatonin alleviates cadmium uptake and toxicity in apple rootstocks.

To examine the potential roles of melatonin in cadmium (Cd) uptake, accumulation and detoxification in Malus plants, we exposed two different apple rootstocks varying greatly in Cd uptake and accumulation to either 0 or 30 µM Cd together with 0 or 100 µM melatonin. Cadmium stress stimulated endogenous melatonin production to a greater extent in the Cd-tolerant Malus baccata Borkh. than in the Cd-susceptible Malus micromalus 'qingzhoulinqin'. Melatonin application attenuated Cd-induced reductions in growth, photosynthesis and enzyme activity, as well as reactive oxygen species (ROS) and malondialdehyde accumulation. Melatonin treatment more effectively restored photosynthesis, photosynthetic pigments and biomass in Cd-challenged M. micromalus 'qingzhoulinqin' than in Cd-stressed M. baccata. Exogenous melatonin lowered root Cd2+ uptake, reduced leaf Cd accumulation, decreased Cd translocation factors and increased root, stem and leaf melatonin contents in both Cd-exposed rootstocks. Melatonin application increased both antioxidant concentrations and enzyme activities to scavenge Cd-induced ROS. Exogenous melatonin treatment altered the mRNA levels of several genes regulating Cd uptake, transport and detoxification including HA7, NRAMP1, NRAMP3, HMA4, PCR2, NAS1, MT2, ABCC1 and MHX. Taken together, these results suggest that exogenous melatonin reduced aerial parts Cd accumulation and mitigated Cd toxicity in Malus plants, probably due to the melatonin-mediated Cd allocation in tissues, and induction of antioxidant defense system and transcriptionally regulated key genes involved in detoxification.

Octahydrocurcumin, a final hydrogenated metabolite of curcumin, possesses superior anti-tumor activity through induction of cellular apoptosis.

The biological activity of curcumin (CUR), a promising naturally occurring dietary compound for the treatment of hepatocellular carcinoma (HCC), was closely associated with its metabolite. Octahydrocurcumin (OHC) is the final hydrogenated metabolite of CUR and has been reported to have potential biological activities. However, difficulties in access have hampered its biological studies. In the current investigation, we designed an efficient synthesis method to produce OHC, and comparatively explored the anti-cancer effect and potential mechanism of OHC and CUR in an H22 ascites tumor-bearing mice model. The results indicated that OHC had a relatively wide margin of safety, and exhibited superior effects to CUR in suppressing the tumor growth, including ascending weight, abdominal circumference, ascites volume and cancer cell viability. OHC significantly induced H22 cell apoptosis by upregulating the p53 expression and downregulating the MDM2 expression. OHC also remarkably decreased the Bcl-2 and Bcl-xl protein expressions, and increased the Bax and Bad expressions in ascitic cells. Furthermore, THC substantially induced the release of cytochrome C, caspase-3, caspase-9 and the cleavage of PARP to induce H22 cell apoptosis. Taken together, OHC was more effective than CUR in suppressing H22-induced HCC through the activation of the mitochondrial apoptosis pathway. OHC may thus be a promising anti-HCC agent.

Patchoulene Epoxide Isolated from Patchouli Oil Suppresses Acute Inflammation through Inhibition of NF-κB and Downregulation of COX-2/iNOS.

According to the GC-MS analysis, compositional variation was observed between samples of patchouli oil, of which an unknown compound identified as patchoulene epoxide (PAO) was found only in the long-stored oil, whose biological activity still remains unknown. Therefore, the present study aimed to evaluate the potential anti-inflammatory activity with three in vivo inflammatory models: xylene-induced ear edema, acetic acid-induced vascular permeability, and carrageenan-induced paw edema. Further investigation into its underlying mechanism on carrageenan-induced paw edema was conducted. Results demonstrated that PAO significantly inhibited the ear edema induced by xylene, lowered vascular permeability induced by acetic acid and decreased the paw edema induced by carrageenan. Moreover, PAO markedly decreased levels of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin-6 (IL-6), prostaglandin E2 (PGE2), and nitric oxide (NO), but increased levels of interleukin-4 (IL-4) and interleukin-10 (IL-10). PAO was also shown to significantly downregulate the protein and mRNA expressions of cyclooxygenase-2 (COX-2) and inducible nitric-oxide synthase (iNOS). Western blot analysis revealed that PAO remarkably inhibited p50 and p65 translocation from the cytosol to the nucleus by suppressing IKKß and IκBα phosphorylation. In conclusion, PAO exhibited potent anti-inflammatory activity probably by suppressing the activation of iNOS, COX-2 and NF-κB signaling pathways.

Integration of Cadmium Accumulation, Subcellular Distribution, and Physiological Responses to Understand Cadmium Tolerance in Apple Rootstocks.

Cadmium (Cd) is a nonessential and highly toxic element causing agricultural problems. However, little information is available about the variation in Cd tolerance among apple rootstocks and its underlying physiological regulation mechanisms. This study investigated Cd accumulation, subcellular distribution, and chemical forms as well as physiological changes among four apple rootstocks exposed to either 0 or 300 µM CdCl2. The results showed that variations in Cd tolerance existed among these rootstocks. Cd exposure caused decline in photosynthesis, chlorophyll and biomass in four apple rootstocks, which was less pronounced in M. baccata, indicating its higher Cd tolerance. This finding was corroborated with higher Cd tolerance indexes (TIs) of the whole plant in M. baccata than those in the other three apple rootstocks. Among the four apple rootstocks, M. baccata displayed the lowest Cd concentrations in roots, wood, and leaves, the smallest total Cd amounts as well as the lowest BCF. In apple rootstocks, it was found that to immobilize Cd in cell wall and soluble fraction (most likely in vacuole) and to convert it into pectate- or protein- integrated forms and undissolved Cd phosphate forms may be the primary strategies to reduce Cd mobility and toxicity. The physiological changes including ROS, carbohydrates and antioxidants were in line with the variations of Cd tolerance among four apple rootstocks. In comparison with the other three apple rootstocks, M. baccata had lower concentrations of ROS in roots and bark, H2O2 in roots and leaves and MDA in roots, wood and bark, but higher concentrations of soluble sugars in bark and starch in roots and leaves, and enhanced antioxidants. These results indicate that M. baccata are more tolerant to Cd stress than the other three apple rootstocks under the current experiment conditions, which is probably related to Cd accumulation, subcellular partitioning and chemical forms of Cd and well-coordinated antioxidant defense mechanisms.

Epiberberine, a natural protoberberine alkaloid, inhibits urease of Helicobacter pylori and jack bean: Susceptibility and mechanism.

In our previous study, Rhizoma Coptidis extract was found to exert more potent inhibitory effect than its major component berberine towards urease from Helicobacter pylori (HPU) and jack bean (JBU). In continuation of our work, the present study was designed to further comparatively investigate the urease inhibitory activities of five major protoberberine alkaloids in Rhizoma Coptidis, namely berberine, palmatine, coptisine, epiberberine, jateorhizine to identify the bioactive constituent, and illuminate the potential mechanism of action. Results indicated that the five protoberberine alkaloids acted as concentration-dependent inactivators of urease with IC50 values ranging between 3.0 and 5087µM for HPU and 2.3->10,000µM for JBU, respectively. Notably, epiberberine (EB) was found to be the most potent inhibitor against both ureases with IC50 values of 3.0±0.01µM for HPU and 2.3±0.01µM for JBU, which was more effective than the standard urease inhibitor, acetohydroxamic acid (83±0.01µM for HPU and 22±0.01µM for JBU, respectively). Further kinetic analysis revealed that the type of EB inhibition against HPU was slow-binding and uncompetitive, with Ki of 10.6±0.01µM, while slow-binding and competitive against JBU with Ki of 4.6±0.01µM. Addition of thiol reagents, such as l-cysteine, glutathione and dithiothreitol, significantly abolished the inhibition, while Ni2+ competitive inhibitors, boric acid and sodium fluoride, synergetically inhibited urease with EB, indicating the obligatory role of the active site sulfhydryl group for the inhibition. In addition, binding of EB with the urease proved to be reversible, as about 65% and 90% enzymatic activity of HPU and JBU, respectively, could be restored by dithiothreitol application. These findings highlighted the potential role of Rhizoma Coptidis protoberberine alkaloids, especially EB, as a lead urease inhibitor in the treatment of diseases associated with ureolytic bacteria. Thus, EB had good potential for further development into a promising therapeutic approach for the treatment of urease-related diseases.