OBJECTIVE: To explore the mechanism of crocin, a major active component of Crocus sativus (Zanghonghua), in regulating amyloid beta (Aβ) generation, endoplasmic reticulum (ER) stress, and autophagy in neuronal cells, with potential therapeutic applications in Alzheimer's disease (AD). METHODS: Mouse neuroblastoma Neuron2a (N2a) cells stably transfected with the human amyloid precursor protein (APP) Swedish mutant was used as a cellular model for AD (N2a/APP). Control cells were vector transfected (N2a/vector). The effects of 3 different doses of crocin on reactive oxygen species (ROS) generation, cytosolic calcium, and apoptosis were evaluated by flow cytometry. Aβ levels were determined by enzyme-linked immunosorbent assay. APP processing and ER stress proteins expressions were determined by Western blot. Autophagosome formation was evaluated by autophagy detection kit and confocal microscope. RESULTS: Crocin inhibited APP expression in N2a/APP cells and promoted α-cleavage of APP processing, while modestly reduced beta-secretase 1 (BACE1) and presenilin 1 (PS1, P<0.05 or P<0.01). ER stress markers, including the binding immunoglobulin protein/78-kD glucose-regulated protein (Bip/GRP78) and C/EBP homologous protein (CHOP), were elevated in N2a/APP cells compared to N2a/vector cells (P<0.05). Crocin could effectively reduce the levels of ER stress (P<0.05 or P<0.01). In addition, crocin enhanced autophagy by promoting formation of autophagosome (P<0.05 or P<0.01). CONCLUSION Crocin significantly inhibited Aβ generation by promoting α-cleavage of APP processing, inhibiting ER stress-associated unfolded protein response, and regulating autophagy.
Endoplasmic Reticulum Stress/drug effects* ; Autophagy/drug effects* ; Animals ; Endoplasmic Reticulum Chaperone BiP ; Mice ; Amyloid beta-Peptides/metabolism* ; Amyloid beta-Protein Precursor/metabolism* ; Carotenoids/pharmacology* ; Humans ; Cell Line, Tumor ; Reactive Oxygen Species/metabolism* ; Apoptosis/drug effects* ; Calcium/metabolism*

Hormesis effect has been observed in the secondary metabolite synthesis of microorganisms induced by rare earth elements. However, the underlying molecular mechanism remains unclear. To analyze the molecular mechanism of the regulatory effect of Rhodotorula mucilaginosa in the presence of lanthanum chloride, different concentrations of lanthanum chloride were added to the fermentation medium of Rhodotorula mucilaginosa, and the carotenoid content was subsequently measured. It was found that the concentrations of La³⁺ exerting the promotional and inhibitory effects were 0-100 mg/L and 100-400 mg/L, respectively. Furthermore, the expression of 33 genes and the synthesis of 55 metabolites were observed to be up-regulated, while the expression of 85 genes and the synthesis of 123 metabolites were found to be down-regulated at the concentration range of the promotional effect. Notably, the expression of carotenoid synthesis-related genes except AL1 was up-regulated. Additionally, the content of β-carotene, lycopene, and astaxanthin demonstrated increases of 10.74%, 5.02%, and 3.22%, respectively. The expression of 5 genes and the synthesis of 91 metabolites were up-regulated, while the expression of 35 genes and the synthesis of 138 metabolites were down-regulated at the concentration range of the inhibitory effect. Meanwhile, the content of β-carotene, lycopene, and astaxanthin decreased by 21.73%, 34.81%, and 35.51%, respectively. In summary, appropriate concentrations of rare earth ions can regulate the synthesis of secondary metabolites by modulating the activities of various enzymes involved in metabolic pathways, thereby exerting the hormesis effect. The findings of this study not only contribute to our comprehension for the mechanism of rare earth elements in organisms but also offer a promising avenue for the utilization of rare earth elements in diverse fields, including agriculture, pharmaceuticals, and healthcare.
Lanthanum/pharmacology* ; Rhodotorula/genetics* ; Carotenoids/metabolism* ; Hormesis/drug effects* ; Fermentation ; Multiomics

Carotenoids are secondary metabolite responsible for colored pigments in plants and microbes (Li et al., 2022). They are a class of C₄₀ tetraterpenoids consisting of eight isoprenoid units, and can be classified into carotenes and xanthophylls on the basis of their functional groups (Saini et al., 2015). Carotenes can be linear (phytoene, phytofluene, and ζ‍-carotene) or branched (β‍-carotene and α‍-carotene). Xanthophylls comprise β,β‍-xanthophylls (β‍-cryptoxanthin, zeaxanthin, violaxanthins, and neoxanthin) and β,ε‍-xanthophylls (α-cryptoxanthin, α-carotene, and lutein). Citrus fruits are complex sources of carotenoids, which are the principal pigments responsible for the typical orange color of most types (Chen, 2020). The difference in total carotenoid content and the diversity of carotenoid isomer proportion also accounts for other colors of citrus fruits, such as yellow, red, and pink (Chen, 2020).
Citrus/metabolism* ; Carotenoids ; Xanthophylls ; Lutein/metabolism* ; Zeaxanthins/metabolism* ; Fruit

CRISPR-Cas9 gene editing technology has been widely used in Saccharomyces cerevisiae.However, the effects of Cas9, as an exogenous protein, on the growth and production of natural products in S.cerevisiae are still unclear.In this study, Cas9 gene was expressed in S.cerevisiae by integration into the genome and construction into vectors, and two natural products, carotenoid and miltiradiene, were selected as the target products to study the effects of Cas9 expression on yeast growth and production capacity.The results showed that whether Cas9 was integrated into the genome or expressed by vectors, Cas9 inhibited the growth of S.cerevisiae, which was more obvious in the form of genome integration.When Cas9 was integrated into the genome, it had no effect on the production of carotenoid and miltiradiene by S.cerevisiae, but when Cas9 was expressed by vectors, the ability of S.cerevisiae to produce carotenoids and miltiradiene was significantly reduced.Therefore, in order to further efficiently knock out Cas9 after gene editing and minimize the adverse impact of Ura3 and Trp1 vectors, this study systematically explored the removal efficiency of the two vectors, and a plasmid capable of efficient gene editing was constructed, which optimized the application of CRISPR-Cas9 gene editing system in S.cerevisiae, and provided reference for the application of gene editing technology based on Cas9.
Biological Products ; CRISPR-Cas Systems ; Carotenoids/metabolism* ; Gene Editing/methods* ; Saccharomyces cerevisiae/metabolism*

Lycopene is an antioxidant which has potential anti-diabetic activity, but the cellular mechanisms have not been clarified. In this study, different concentrations of lycopene were used to treat pancreatic alpha and beta cell lines, and the changes of cell growth, cell apoptosis, cell cycle, reactive oxygen species (ROS), ATP levels and expression of related cytokines were determined. The results exhibited that lycopene did not affect cell growth, cell apoptosis, cell cycle, ROS and ATP levels of alpha cells, while it promoted the growth of beta cells, increased the ratio of S phase, reduced the ROS levels and increased the ATP levels of beta cells. At the same time, lycopene treatment elevated the mRNA expression levels of tnfα, tgfβ and hif1α in beta cells. These findings suggest that lycopene plays cell-specific role and activates pancreatic beta cells, supporting its application in diabetes therapy.
Adenosine Triphosphate ; metabolism ; Apoptosis ; Carotenoids ; pharmacology ; Cell Cycle ; Cells, Cultured ; Cytokines ; metabolism ; Glucagon-Secreting Cells ; drug effects ; Humans ; Insulin-Secreting Cells ; drug effects ; Lycopene ; pharmacology ; Reactive Oxygen Species ; metabolism

BACKGROUND: Endothelial adhesion molecule expression induced by pro-inflammatory cytokine plays an important role in vascular endothelial cell injury, leading to vascular disease. Allium tuberosum (AT), which is used as a functional food, has a thrombolytic effect. It contains vitamin A, vitamin C, carbohydrate, calcium, iron, and phosphorus. There are many carotenes that turn into vitamin A in the body. Also, it helps blood circulation and stimulates metabolism. The purpose of the this study was to estimate the anti-inflammatory effects of the AT extract. METHODS: Human vascular endothelial cells were pre-treated with 100 μg/mL AT extract for 30 minutes and subsequently co-treated with TNF-α (10 ng/mL) and AT extract (100 μg/mL) for 1, 4, and 6 hours. After treatment, the cells were lysed and used for quantitative reverse transcription PCR, Western blot analysis, and monocyte adhesion assay. RESULTS: We examined the effect of the AT extract on inflammatory gene expression in TNF-α-induced human umbilical vein endothelial cells (HUVECs). The extract reduced the expression levels of mRNA and protein of intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 in TNF-α-stimulated HUVECs. It also inhibited the TNF-α-induced phosphorylation of the NF-κB p65 subunit and degradation of IκBα. Furthermore, the AT extract prevented the increased adhesion capacity of monocyte to TNF-α-stimulated vascular endothelial cells by reducing ICAM-1 and VCAM-1 expression. CONCLUSIONS: The AT extract has preventive and anti-inflammatory effect against vascular disease and has potential for supporting prevention against the early process of atherosclerosis.
Allium* ; Ascorbic Acid ; Atherosclerosis ; Blood Circulation ; Blotting, Western ; Calcium ; Carotenoids ; Chive* ; Endothelial Cells* ; Functional Food ; Gene Expression ; Human Umbilical Vein Endothelial Cells ; Humans* ; Inflammation* ; Intercellular Adhesion Molecule-1 ; Iron ; Metabolism ; Monocytes ; Necrosis* ; NF-kappa B ; Phosphorus ; Phosphorylation ; Polymerase Chain Reaction ; Reverse Transcription ; RNA, Messenger ; Vascular Cell Adhesion Molecule-1 ; Vascular Diseases ; Vitamin A

To explore the influence of low light on the synthesis of carotenoids, chlorophyll and the adaptability of transgenic plants with tomato Solanum lycopersicon L. GGPS2 gene, we constructed a vector containing a GGPS2 gene with green fluorescent protein (GFP) as report gene under the control of a cauliflower mosaic virus 35S promoter and introduced it into tobacco Nicotiana tabacum L. cv. Wisconsin 38 by Agrobacterium tumefaciens-mediated transformation. PCR analysis of the DNA from kanamycin resistant tobacco indicated that the transgenic tobacco containing the nptII gene, SlaGGPS2 gene and without contamination of Agrobacterium. We also detected the root tip of kanamycin resistant tobacco showing characteristic fluorescence. The contents of carotenoid, chlorophyll and photosynthesis of transgenic tobacco increased in comparison with wild tobacco after low light treatment. In addition, leaf mass per unit area, total dry weight, ratio of root to shoot in transgenic tobacco were all higher than that of the wild tobacco, which proved that the transgenic tobacco could increase the accumulation of biomass and promote it transport to root. The transgenic tobacco with SlaGGPS2 gene can increase the contents of carotenoid, chlorophyll, enhance the photosynthetic rate, promote the biomass accumulation and its distribution to root. Hence, the transgenic tobacco with SlaGGPS2 gene had increased low light tolerance and the SlaGGPS2 gene maybe can be used in other crops.
Agrobacterium tumefaciens ; Carotenoids ; analysis ; Chlorophyll ; analysis ; Gene Expression Regulation, Plant ; Genetic Vectors ; Light ; Lycopersicon esculentum ; genetics ; Photosynthesis ; Plants, Genetically Modified ; metabolism ; radiation effects ; Tobacco ; metabolism ; radiation effects

Crocetin, a naturally occurring carotenoid, possesses antioxidant and antiatherosclerotic properties, of which the underlying mechanism remains unclear. In the present study, we examined the effects of crocetin (0.1, 1, 10 μmol·L(-1)) on angiotensin II (Ang II, 0.1 μmol·L(-1)) induced expression of vascular cell adhesion molecule-1 (VCAM-1) in human umbilical vein endothelial cells (HUVECs) and monocyte-endothelial cell adhesion. The effects of crocetin on the activation of nuclear factor kappa B (NF-κB) and intracellular reactive oxygen species (ROS) were also observed. The results demonstrated that crocetin notably suppressed Ang II induced NF-κB activation (P<0.01) and VCAM-1 expression (P<0.05, P<0.01) in HUVECs, accompanied by a markedly reduced monocyte-endothelial cell adhesion (P<0.05, P<0.01). In addition, preincubation with crocetin resulted in a significant enhancement of cellular antioxidant capacity (P<0.05, P<0.01), while Ang II induced intracellular ROS decreased markedly (P<0.05, P<0.01). These results indicated that crocetin was capable of suppressing Ang II induced VCAM-1 expression and monocyte-endothelial cell adhesion by suppression of NF-κB activation, which might be derived from the enhancement of antioxidant capacity and subsequent reduction of intracellular ROS.
Angiotensin II ; metabolism ; Antioxidants ; pharmacology ; Carotenoids ; pharmacology ; Cell Adhesion ; drug effects ; Human Umbilical Vein Endothelial Cells ; cytology ; drug effects ; metabolism ; Humans ; Monocytes ; cytology ; NF-kappa B ; metabolism ; Reactive Oxygen Species ; metabolism ; Vascular Cell Adhesion Molecule-1 ; metabolism

BACKGROUNDEpidemiological studies have shown that lycopene has anti-prostate cancer effect. In vitro tests also confirmed that it can promote apoptosis of prostate cancer cells. We investigated the effect of whole-tomato supplement lycopene on the prostate-specific antigen velocity in selected prostate cancer patients.

METHODSTwenty selected prostate cancer patients were given whole-tomato supplement lycopene 10 mg per day for about 6 months. Blood samples of patients were collected weekly to measure serum prostate-specific antigen (PSA) values. PSA velocity slope, which reflects the change of PSA, and the degree of change were also calculated. By comparing the values of average PSA velocity slope (rise or fall of PSA) before and after the administration of lycopene, the effect of lycopene can be evaluated. Blood chemistry analysis was regular followed as safety control.

RESULTSThree patients in the research group withdrew within 3 weeks because of inability to conform. The rest 17 patients continued for an average period of 6 months. Two patients withdrew because of cancer progression (PSA rise) who later received active treatment. The average fall in PSA was equivalent to 2.56% over (i.e. an average slope/d of -0.000 28) the first 3 months. In the last 3 months, average fall in PSA was equivalent to 31.58% (i.e. an average slope/d of -0.003 51). The Wilcoxon rank-sum test showed a statistically significant decrease of PSA velocity slope overall (P = 0.000 9). Analysis of the PSA doubling time (pre- vs. post-treatment) showed a median increase over 3 months but this was not statistically significant (P = 0.21). No toxic side effect was observed during the whole process. The results indicate that the average PSA change is "decline" in patients, and the degree of the decline is accelerated.

CONCLUSIONAdministration of lycopene was able to reduce PSA velocity in this study group.

Aged ; Carotenoids ; therapeutic use ; Dietary Supplements ; Female ; Humans ; Male ; Prostate-Specific Antigen ; metabolism ; Prostatic Neoplasms ; blood ; drug therapy

For microbial production of lycopene, the lycopene synthetic genes from Pantoea agglomerans were integrated into Saccharomyces cerevisiae strain BY4742, to obtain strain ZD-L-000 for production of 0.17 mg · L(-1) lycopene. Improving supplies of isoprenoid precursors was then investigated for increasing lycopene production. Four key genes were chosen to be overexpressed, inclu- ding truncated 3-hydroxy-3-methylglutaryl-CoA reductase gene (tHMG1), which is the major rate-limiting enzyme in the mevalonate (MVA) pathway, a mutated global regulatory factor gene (upc2.1), a fusion gene of FPP synthase (ERG20) and endogenous GGPP synthase (BTS1), which is a key enzyme in the diterpenoid synthetic pathway, and GGPP synthase gene (SaGGPS) from Sulfolobus acidocaldarius. Over-expression of upc2.1 could not improve lycopene production, while over-expression of tHMGI , BTS1-ERG20 and SaGGPS genes led to 2-, 16. 9- and20. 5-fold increase of lycopene production, respectively. In addition, three effective genes, tHMG1, BTS1-ERG20 and SaGGPS, were integrated into rDNA sites of ZD-L-000, resulting in strain ZD-L-201 for production of 13.23 mg · L(-1) lycopene, which was 77-fold higher than that of the parent strain. Finally, two-phase extractive fermentation was performed. The titer of lycopene increased 10-fold to 135.21 mg · L(-1). The engineered yeast strains obtained in this work provided the basis for fermentative production of lycopene.
Bacterial Proteins ; genetics ; metabolism ; Biosynthetic Pathways ; Carotenoids ; biosynthesis ; Genes, Synthetic ; Genetic Engineering ; Pantoea ; enzymology ; genetics ; Saccharomyces cerevisiae ; genetics ; metabolism