Capilliposide B inhibits the migration of prostate cancer by inducing autophagy through the ROS/AMPK/mTOR pathway.

Capilliposide B (CPS-B), a novel oleanane triterpenoid saponin derived from Lysimachia capillipes Hemsl, is a potent anticancer agent. However, its anticancer mechanism remains elusive. In the present study, we demonstrated the potent anti-tumor activity and molecular mechanism of CPS-B both in vitro and in vivo. Proteomic analysis using isobaric tags for relative and absolute quantitation techniques suggested that CPS-B modulated autophagy in prostate cancer (PC). Moreover, Western blotting showed that both autophagy and epithelial-mesenchymal transition occurred place after CPS-B treatment in vivo, which was also proven in PC-3 cancer cells. We deduced that CPS-B inhibited migration by inducing autophagy. We examined the accumulation of reactive oxygen species (ROS) in cells, and in downstream pathways, LKB1 and AMPK were activated while mTOR was inhibited. Transwell experiment results showed that CPS-B inhibited the metastasis of PC-3 cells and that this effect was significantly attenuated after pretreatment with chloroquine, indicating that CPS-B inhibited metastasis via autophagy induction. Altogether, these data suggest that CPS-B is a potential therapeutic agent for cancer treatment that acts by inhibiting migration through the ROS/AMPK/mTOR signaling pathway.

Idelalisib inhibits experimental proliferative vitroretinopathy.

Proliferative vitreoretinopathy (PVR) is a fibrotic eye disease that develops after rhegmatogenous retinal detachment surgery and open-globe traumatic injury. Idelalisib is a specific inhibitor of phosphoinositide 3-kinase (PI3K) δ. While PI3Kδ is primarily expressed in leukocytes, its expression is also considerably high in retinal pigment epithelial (RPE) cells, which play a crucial part in the PVR pathogenesis. Herein we show that GeoMx Digital Spatial Profiling uncovered strong expression of fibronectin in RPE cells within epiretinal membranes from patients with PVR, and that idelalisib (10 µM) inhibited Akt activation, fibronectin expression and collagen gel contraction induced by transforming growth factor (TGF)-ß2 in human RPE cells. Furthermore, we discovered that idelalisib at a vitreal concentration of 10 µM, a non-toxic dose to the retina, prevented experimental PVR induced by intravitreally injected RPE cells in rabbits assessed by experienced ophthalmologists using an indirect ophthalmoscope plus a + 30 D fundus lens, electroretinography, optical coherence tomography and histological analysis. These data suggested idelalisib could be harnessed for preventing patients from PVR.

Guangsangon E triggers mitochondria dysfunction and mitophagy in triple-negative breast cancer and leads to non-apoptotic cell death.

Guangsangon E (GSE) is a natural product separated from Morus alba L. It has been reported to treat lung cancer through autophagy. However, whether GSE is effective in repressing triple-negative breast cancer (TNBC) cells is yet to be elucidated. In the present study, GSE inhibited cell growth of MDA-MB-231, MDA-MB-453, and MDA-MB-468 cells. Moreover, GSE induced mitochondrial dysfunction, including membrane potential loss, mitochondria fission, and reactive oxygen species accumulation, and finally led to mitophagy-related non-apoptotic cell death. In the xenograft tumor nude mice, GSE treatment significantly reduced the size and weight of MDA-MB-231 tumors. The tumor inhibition rates of GSE treatment were 49.68% (low-dose) and 48.73% (high-dose). In summary, GSE is a potential anticancer drug available for treating TNBC with apoptosis resistance.

LC-MS/MS based metabolomics and proteomics reveal candidate biomarkers and molecular mechanism of early IgA nephropathy.

BACKGROUND: Immunoglobulin A nephropathy (IgAN), a globally common primary chronic glomerulopathy, is one of the leading causes of end-stage renal disease. However, the underlying mechanisms of IgAN have yet to be demonstrated. There were no adequate and reliable plasma biomarkers for clinical diagnosis, especially at the early stage. In the present study, integrative proteomics and metabolomics were aimed at exploring the mechanism of IgAN and identifying potential biomarkers. METHODS: Plasma from IgAN and healthy individuals were collected and analyzed in a randomized controlled manner. Data-independent acquisition quantification proteomics and mass spectrometry based untargeted metabolomics techniques were used to profile the differentially expressed proteins (DEPs) and differentially abundant metabolites (DAMs) between two groups and identify potential biomarkers for IgAN from health at the early stage. Disease-related pathways were screened out by clustering and function enrichment analyses of DEPs and DAMs. And the potential biomarkers for IgAN were identified through the machine learning approach. Additionally, an independent cohort was used to validate the priority candidates by enzyme-linked immunosorbent assay (ELISA). RESULTS: Proteomic and metabolomic analyses of IgAN plasma showed that the complement and the immune system were activated, while the energy and amino acid metabolism were disordered in the IgAN patients. PRKAR2A, IL6ST, SOS1, and palmitoleic acid have been identified as potential biomarkers. Based on the AUC value for the training and test sets, the classification performance was 0.994 and 0.977, respectively. The AUC of the external validation of the four biomarkers was 0.91. CONCLUSION: In this study, we combined proteomics and metabolomics techniques to analyze the plasma of IgAN patients and healthy individuals, constructing a biomarker panel, which could provide new insights and provide potential novel molecular diagnoses for IgAN.

Tandem mass tag-based proteomic analysis of endoplasmic reticulum proteins in mulberry leaves under ultraviolet-B and dark stress.

Mulberry leaves have been used in traditional Chinese medicine due to their antioxidant, antidiabetic, and antihyperlipidemic properties. A previous study showed that ultraviolet-B radiation followed by dark incubation could improve the contents of active ingredients in mulberry leaves, such as moracin N and chalcomoracin. The endoplasmic reticulum (ER) serves as a protein quality control center and the location for protein synthesis, which is involved in the response to the environmental stress in plants. To investigate the mechanisms in response to ultraviolet-B radiation followed by dark incubation (UV + D), ER proteomics was performed on mulberry leaves. The ER protein markers, glucose-regulated protein (GRP78), and calnexin (CNX), were significantly higher in the ER fraction than in the total protein fraction, indicating that the ER was purified. Compared to the control, the abundance of protein disulfide isomerase, UDP-glucose glycoprotein glucosyltransferase, CNX, and calreticulin proteins decreased, while of the abundance of heat shock-related proteins increased under stress. P450 enzyme system-related proteins and ribosomal proteins showed significant increases. These results suggest that under UV + D stress, mulberry leaves activated the cell redox and ER quality control systems, enhancing protein synthesis and weakening N-glycan biosynthesis in the ER to resist the damage.

A Quassinoid Diterpenoid Eurycomanone from Eurycoma longifolia Jack Exerts Anti-Cancer Effect through Autophagy Inhibition.

Eurycomanone (EN) is one of the representative quassinoid diterpenoids from roots of Eurycoma longifolia Jack, a natural medicine that is widely distributed in Southeast Asia. Previous studies showed that EN induces cancer cell apoptosis and exhibits anti-cancer activity, but the molecular mechanism of EN against cancer has still not been elucidated. In this study, we examined the regulatory effect of EN on autophagy to reveal the mechanism of EN-mediated colon cancer growth inhibition. First, we found that EN is able to inhibit colon cancer cell proliferation and colony formation. The angiogenesis level in cancer cells was inhibited as well. Next, the treatment of EN led to the suppression of autophagy, which was characterized by the downregulation of the LC3-II level and the formation of GFP-LC3 puncta under EN treatment in colon cancer. Moreover, we revealed that the mTOR signaling pathway was activated by EN in a time- and concentration-dependent manner. Finally, autophagy induction protected colon cancer cells from EN treatment, suggesting that autophagy improves cell survival. Taken together, our findings revealed the mechanism of EN against colon cancer through inhibiting autophagy and angiogenesis in colon cancer, supporting that the autophagy inhibitor EN could be developed to be a novel anti-cancer agent.

Chalcomoracin prevents vitreous-induced activation of AKT and migration of retinal pigment epithelial cells.

Retinal pigment epithelial (RPE) cells are the major cell type in the epi- or sub-retinal membranes in the pathogenesis of proliferative vitreoretinopathy (PVR), which is a blinding fibrotic eye disease and still short of effective medicine. The purpose of this study is to demonstrate whether Chalocomoracin (CMR), a novel purified compound from fungus-infected mulberry leaves, is able to inhibit vitreous-induced signalling events and cellular responses intrinsic to PVR. Our studies have revealed that the CMR IC50 for ARPE-19 cells is 35.5 µmol/L at 72 hours, and that 5 µmol/L CMR inhibits vitreous-induced Akt activation and p53 suppression; in addition, we have discovered that this chemical effectively blocks vitreous-stimulated proliferation, migration and contraction of ARPE-19 cells, suggesting that CMR is a promising PVR prophylactic.

Investigation of phytochemical composition and metabolite profiling in vivo of Beta vulgaris L.

RATIONALE: Beta vulgaris L. has attracted increasing attention because of its broad application. The root of B. vulgaris L. (beetroot) possesses many excellent biological properties such as antianemic, anti-inflammatory, antihypertensive, antioxidant, anticarcinogenic, antipyretic, antibacterial, detoxicant, and diuretic. The chemical constituents of beetroot play a major role in the research on beetroot application and development. At present, no systematic identification study that focuses on the chemical constituents of beetroot has been reported. METHODS: This study investigated a three-step strategy comprising phytochemical profiling, prototype profiling, and metabolism of its correlative metabolites in vivo using ultra-performance liquid chromatography tandem quadruple time-of-flight mass spectrometry (UPLC-QTOF-MS/MS). RESULTS: UPLC-QTOF-MS/MS technique proved to be a rapid, sensitive, and reliable method for monitoring the specific ingredients as well as the whole chemical constituents in beetroot. In sum, 95 phytochemical compounds, 51 prototype compounds, and 37 derived metabolites in vivo were found in beetroot. CONCLUSIONS: The main metabolic pathways were sulfonation, glucuronidation, methylation/sulfonation, and methylation. The present findings provided the phytochemical basis both in vitro and in vivo for future application.

A novel Diels-Alder adduct of mulberry leaves exerts anticancer effect through autophagy-mediated cell death.

Guangsangon E (GSE) is a novel Diels-Alder adduct isolated from leaves of Morus alba L, a traditional Chinese medicine widely applied in respiratory diseases. It is reported that GSE has cytotoxic effect on cancer cells. In our research, we investigated its anticancer effect on respiratory cancer and revealed that GSE induces autophagy and apoptosis in lung and nasopharyngeal cancer cells. We first observed that GSE inhibits cell proliferation and induces apoptosis in A549 and CNE1 cells. Meanwhile, the upregulation of autophagosome marker LC3 and increased formation of GFP-LC3 puncta demonstrates the induction of autophagy in GSE-treated cells. Moreover, GSE increases the autophagy flux by enhancing lysosomal activity and the fusion of autophagosomes and lysosomes. Next, we investigated that endoplasmic reticulum (ER) stress is involved in autophagy induction by GSE. GSE activates the ER stress through reactive oxygen species (ROS) accumulation, which can be blocked by ROS scavenger NAC. Finally, inhibition of autophagy attenuates GSE-caused cell death, termed as "autophagy-mediated cell death." Taken together, we revealed the molecular mechanism of GSE against respiratory cancer, which demonstrates great potential of GSE in the treatment of representative cancer.

A two-step strategy for quality control of Xin-Yu-Tie-Pian, an ointment patch.

Xin-Yu-Tie-Pian, an ointment patch which is composed of Tetradium ruticarpum and Asarum sieboldii Miquel, can be used for curing recurrent oral ulcers owing to its good bioactivities. Currently, the lack of a method for its quality evaluation hinders the development and clinical application of Xin-Yu-Tie-Pian. Thus, it is necessary to perform research on quality control. The chromatographic fingerprint, as an identification method, and the simultaneous determination method for two bioactive constituents, evodiamine and rutecarpine, can be used to evaluate the quality of traditional medicine. In this study, a two-step strategy including fingerprint analysis for identification and a simultaneous determination method for two bioactive constituents was performed for Xin-Yu-Tie-Pian quality control. The fingerprint analysis was validated by stability, precision and repeatability tests and a similarity evaluation was performed with 10 selected characteristic fingerprint peaks of 10 batches of Xin-Yu-Tie-Pian patch. Meanwhile, the simultaneous determination method was evaluated by methodological experiments, including linearity, accuracy, repeatability, stability and feasibility. Finally, the results indicate that this two-step strategy, including HPLC fingerprint analysis and simultaneous determination method, can be successfully applied for the assessment of the quality and quantity of Xin-Yu-Tie-Pian.

Morphophysiological and Proteomic Responses on Plants of Irradiation with Electromagnetic Waves.

Electromagnetic energy is the backbone of wireless communication systems, and its progressive use has resulted in impacts on a wide range of biological systems. The consequences of electromagnetic energy absorption on plants are insufficiently addressed. In the agricultural area, electromagnetic-wave irradiation has been used to develop crop varieties, manage insect pests, monitor fertilizer efficiency, and preserve agricultural produce. According to different frequencies and wavelengths, electromagnetic waves are typically divided into eight spectral bands, including audio waves, radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays. In this review, among these electromagnetic waves, effects of millimeter waves, ultraviolet, and gamma rays on plants are outlined, and their response mechanisms in plants through proteomic approaches are summarized. Furthermore, remarkable advancements of irradiating plants with electromagnetic waves, especially ultraviolet, are addressed, which shed light on future research in the electromagnetic field.

Phosphoinositide 3-kinase δ inactivation prevents vitreous-induced activation of AKT/MDM2/p53 and migration of retinal pigment epithelial cells.

Phosphoinositide 3-kinases (PI3Ks) are a family of lipid kinases that play a critical role in transmitting signals from cell-surface molecules to intracellular protein effectors. Key PI3Ks include PI3Kα, PI3Kß, and PI3Kδ, which are regulated by receptors. The signaling pathway comprising the PI3Ks, along with a Ser/Thr kinase (AKT), a proto-oncogene product (mouse double minute (MDM)2), and a tumor suppressor protein (p53), plays an essential role in experimental proliferative vitreoretinopathy (PVR), which is a fibrotic blinding eye disorder. However, which PI3K isoforms are involved in PVR is unknown. A major characteristic of PVR is the formation of epi (or sub)-retinal membranes that consist of extracellular matrix and cells, including retinal pigment epithelium (RPE) cells, glial cells, and macrophages. RPE cells are considered key players in PVR pathogenesis. Using immunoblotting and immunofluorescence analyses, we herein provide the evidence that PI3Kδ is highly expressed in human RPEs when it is primarily expressed in leukocytes. We also found that PI3Kδ inactivation through two approaches, CRISPR/Cas9-mediated depletion and a PI3Kδ-specific inhibitor (idelalisib), not only blocks vitreous-induced activation of AKT and MDM2 but also abrogates a vitreous-stimulated decrease in p53. Furthermore, we demonstrate that PI3Kδ inactivation prevents vitreous-induced proliferation, migration, and contraction of human RPEs. These results suggest that PI3Kδ may represent a potential therapeutic target for RPE-related eye diseases, including PVR.

Proteomic Analysis of Irradiation with Millimeter Waves on Soybean Growth under Flooding Conditions.

Improving soybean growth and tolerance under environmental stress is crucial for sustainable development. Millimeter waves are a radio-frequency band with a wavelength range of 1-10 mm that has dynamic effects on organisms. To investigate the potential effects of millimeter-waves irradiation on soybean seedlings, morphological and proteomic analyses were performed. Millimeter-waves irradiation improved the growth of roots/hypocotyl and the tolerance of soybean to flooding stress. Proteomic analysis indicated that the irradiated soybean seedlings recovered under oxidative stress during growth, whereas proteins related to glycolysis and ascorbate/glutathione metabolism were not affected. Immunoblot analysis confirmed the promotive effect of millimeter waves to glycolysis- and redox-related pathways under flooding conditions. Sugar metabolism was suppressed under flooding in unirradiated soybean seedlings, whereas it was activated in the irradiated ones, especially trehalose synthesis. These results suggest that millimeter-waves irradiation on soybean seeds promotes the recovery of soybean seedlings under oxidative stress, which positively regulates soybean growth through the regulation of glycolysis and redox related pathways.

Phosphoproteomics Reveals the Biosynthesis of Secondary Metabolites in Catharanthus roseus under Ultraviolet-B Radiation.

Ultraviolet (UV)-B radiation acts as an elicitor to enhance the production of secondary metabolites in medicinal plants. To investigate the mechanisms, which lead to secondary metabolites in Catharanthus roseus under UVB radiation, a phosphoproteomic technique was used. ATP content increased in the leaves of C. roseus under UVB radiation. Phosphoproteins related to calcium such as calmodulin, calcium-dependent kinase, and heat shock proteins increased. Phosphoproteins related to protein synthesis/modification/degradation and signaling intensively changed. Metabolomic analysis indicated that the metabolites classified with pentoses, aromatic amino acids, and phenylpropanoids accumulated under UVB radiation. Phosphoproteomic and immunoblot analyses indicated that proteins related to glycolysis and the reactive-oxygen species scavenging system were changed under UVB radiation. These results suggest that UVB radiation activates the calcium-related pathway and reactive-oxygen species scavenging system in C. roseus. These changes lead to the upregulation of proteins, which are responsible for the redox reactions in secondary metabolism and are important for the accumulation of secondary metabolites in C. roseus under UVB radiation.

Transcriptional regulation of Lonicera japonica Thunb. during flower development as revealed by comprehensive analysis of transcription factors.

BACKGROUND: Lonicera japonica Thunb. flower has been used for the treatment of various diseases for a long time and attracted many studies on its potential effects. Transcription factors (TFs) regulate extensive biological processes during plant development. As the restricted reports of L. japonica on TFs, our work was carried out to better understand the TFs' regulatory roles under different developmental stages in L. japonica. RESULTS: In this study, 1316 TFs belonging to 52 families were identified from the transcriptomic data, and corresponding expression profiles during the L. japonica flower development were comprehensively analyzed. 917 (69.68%) TFs were differentially expressed. TFs in bHLH, ERF, MYB, bZIP, and NAC families exhibited obviously altered expression during flower growth. Based on the analysis of differentially expressed TFs (DETFs), TFs in MYB, WRKY, NAC and LSD families that involved in phenylpropanoids biosynthesis, senescence processes and antioxidant activity were detected. The expression of MYB114 exhibited a positive correlation with the contents of luteoloside; Positive correlation was observed among the expression of MYC12, chalcone synthase (CHS) and flavonol synthase (FLS), while negative correlation was observed between the expression of MYB44 and the synthases; The expression of LSD1 was highly correlated with the expression of SOD and the total antioxidant capacity, while the expression of LOL1 and LOL2 exhibited a negative correlation with them; Many TFs in NAC and WRKY families may be potentially involved in the senescence process regulated by hormones and reactive oxygen species (ROS). The expression of NAC19, NAC29, and NAC53 exhibited a positive correlation with the contents of ABA and H2O2, while the expression of WRKY53, WRKY54, and WRKY70 exhibited a negative correlation with the contents of JA, SA and ABA. CONCLUSIONS: Our study provided a comprehensive characterization of the expression profiles of TFs during the developmental stages of L. japonica. In addition, we detected the key TFs that may play significant roles in controlling active components biosynthesis, antioxidant activity and flower senescence in L. japonica, thereby providing valuable insights into the molecular networks underlying L. japonica flower development.

A metabolomic strategy revealed the role of JA and SA balance in Clematis terniflora DC. Response to UVB radiation and dark.

Clematis terniflora DC. is a valuable resource with potential high pharmaceutical value. Proteomic, transcriptomic and metabolomic analyses of C. terniflora that has been exposed to high levels of UVB irradiation and dark conditions (HUVB + D) have revealed the mechanisms underlying its medicinal potential. However, the signal transduction pathways and the mechanisms of regulation for the accumulation of secondary metabolites remain unclear. In this study, we show that the jasmonic acid (JA) and salicylic acid (SA) signals were activated in C. terniflora in response to HUVB + D. Metabolomic analysis demonstrated that the perturbation in JA and SA balance led to additional reallocation of carbon and nitrogen resources. Evaluating the fold change ratios of differentially changed metabolites proved that JA signal enhanced the transformation of nitrogen to carbon through the 4-aminobutyric acid (GABA) shunt pathway, which increased the carbon reserve to be utilized in the production of secondary metabolites. However, SA signal induced the synthesis of proline, while avoiding the accumulation of secondary metabolites. Over all, the results indicate that the co-increase of JA and SA reconstructed the dynamic stability of transformation from nitrogen to carbon, which effectively enhanced the oxidative defense to HUVB + D in C. terniflora by increasing the secondary metabolites.

Organ-Specific Analysis of Morus alba Using a Gel-Free/Label-Free Proteomic Technique.

Morus alba is an important medicinal plant that is used to treat human diseases. The leaf, branch, and root of Morus can be applied as antidiabetic, antioxidant, and anti-inflammatory medicines, respectively. To explore the molecular mechanisms underlying the various pharmacological functions within different parts of Morus, organ-specific proteomics were performed. Protein profiles of the Morus leaf, branch, and root were determined using a gel-free/label-free proteomic technique. In the Morus leaf, branch, and root, a total of 492, 414, and 355 proteins were identified, respectively, including 84 common proteins. In leaf, the main function was related to protein degradation, photosynthesis, and redox ascorbate/glutathione metabolism. In branch, the main function was related to protein synthesis/degradation, stress, and redox ascorbate/glutathione metabolism. In root, the main function was related to protein synthesis/degradation, stress, and cell wall. Additionally, organ-specific metabolites and antioxidant activities were analyzed. These results revealed that flavonoids were highly accumulated in Morus root compared with the branch and leaf. Accordingly, two root-specific proteins named chalcone flavanone isomerase and flavonoid 3,5-hydroxylase were accumulated in the flavonoid pathway. Consistent with this finding, the content of the total flavonoids was higher in root compared to those detected in branch and leaf. These results suggest that the flavonoids in Morus root might be responsible for its biological activity and the root is the main part for flavonoid biosynthesis in Morus.

Molecular Characterization of a Geranyl Diphosphate-Specific Prenyltransferase Catalyzing Stilbenoid Prenylation from Morus alba.

Pharmaceutically active compounds from medical plants are attractive as a major source for new drug development. Prenylated stilbenoids with increased lipophilicity are valuable secondary metabolites which possess a wide range of biological activities. So far, many prenylated stilbenoids have been isolated from Morus alba but the enzyme responsible for the crucial prenyl modification remains unknown. In the present study, a stilbenoid-specific prenyltransferase (PT), termed Morus alba oxyresveratrol geranyltransferase (MaOGT), was identified and functionally characterized in vitro. MaOGT recognized oxyresveratrol and geranyl diphosphate (GPP) as natural substrates, and catalyzed oxyresveratrol prenylation. Our results indicated that MaOGT shared common features with other aromatic PTs, e.g. multiple transmembrane regions, conserved functional domains and targeting to plant plastids. This distinct PT represents the first stilbenoid-specific PT accepting GPP as a natural prenyl donor, and could help identify additional functionally varied PTs in moraceous plants. Furthermore, MaOGT might be applied for high-efficiency and large-scale prenylation of oxyresveratrol to produce bioactive compounds for potential therapeutic applications.

Comparative Proteomic Analysis Reveals Elevated Capacity for Photosynthesis in Polyphenol Oxidase Expression-Silenced Clematis terniflora DC. Leaves.

Polyphenol oxidase (PPO) catalyzes the o-hydroxylation of monophenols and oxidation of o-diphenols to quinones. Although the effects of PPO on plant physiology were recently proposed, little has been done to explore the inherent molecular mechanisms. To explore the in vivo physiological functions of PPO, a model with decreased PPO expression and enzymatic activity was constructed on Clematis terniflora DC. using virus-induced gene silencing (VIGS) technology. Proteomics was performed to identify the differentially expressed proteins (DEPs) in the model (VC) and empty vector-carrying plants (VV) untreated or exposed to high levels of UV-B and dark (HUV-B+D). Following integration, it was concluded that the DEPs mainly functioned in photosynthesis, glycolysis, and redox in the PPO silence plants. Mapman analysis showed that the DEPs were mainly involved in light reaction and Calvin cycle in photosynthesis. Further analysis illustrated that the expression level of adenosine triphosphate (ATP) synthase, the content of chlorophyll, and the photosynthesis rate were increased in VC plants compared to VV plants pre- and post HUV-B+D. These results indicate that the silence of PPO elevated the plant photosynthesis by activating the glycolysis process, regulating Calvin cycle and providing ATP for energy metabolism. This study provides a prospective approach for increasing crop yield in agricultural production.

SWATH-based quantitative proteomics reveals the mechanism of enhanced Bombyx mori nucleopolyhedrovirus-resistance in silkworm reared on UV-B treated mulberry leaves.

Bombyx mori nucleopolyhedrovirus (BmNPV) is one of the most acute infectious diseases in silkworm, which has led to great economic loss in sericulture. Previous study showed that the content of secondary metabolites in mulberry leaves, particularly for moracin N, was increased after UV-B irradiation. In this study, the BmNPV resistance of silkworms reared on UV-B treated and moracin N spread mulberry leaves was improved. To uncover the mechanism of enhanced BmNPV resistance, silkworm midguts from UV-B treated mulberry leaves (BUM) and moracin N (BNM) groups were analyzed by SWATH-based proteomic technique. Of note, the abundance of ribosomal proteins in BUM and BNM groups was significantly changed to maintain the synthesis of total protein levels and cell survival. While, cytochrome c oxidase subunit II, calcium ATPase and programmed cell death 4 involved in apoptotic process were up-regulated in BNM group. Expressions of lipase-1, serine protease precursor, Rab1 protein, and histone genes were increased significantly in BNM group. These results suggest that moracin N might be the main active component in UV-B treated mulberry leaves which could improve the BmNPV-resistance of silkworm through promoting apoptotic cell death, enhancing the organism immunity, and regulating the intercellular environment of cells in silkworm. It also presents an innovative process to reduce the mortality rate of silkworms infected with BmNPV.