δ-Tocotrienol feeding modulates gene expression of EIF2, mTOR, protein ubiquitination through multiple-signaling pathways in chronic hepatitis C patients

Combined metabolic and enzymatic engineering for de novo biosynthesis of δ-tocotrienol in Yarrowia lipolytica

δ-Tocotrienol, an isomer of vitamin E with anti-inflammatory, neuroprotective and anti-coronary arteriosclerosis properties, is widely used in health care, medicine and other fields. Microbial synthesis of δ-tocotrienol offers significant advantages over plant extraction and chemical synthesis methods, including increased efficiency, cost-effectiveness and environmental sustainability. However, limited precursor availability and low catalytic efficiency of key enzymes remain major bottlenecks in the biosynthesis of δ-tocotrienol. In this study, we assembled the complete δ-tocotrienol biosynthetic pathway in Yarrowia lipolytica and enhanced the precursor supply, resulting in a titre of 102.8 mg/L. The catalytic efficiency of the rate-limiting steps in the pathway was then enhanced through various strategies, including fusion expression of key enzymes homogentisate phytyltransferaseand and tocopherol cyclase, semi-rational design of SyHPT and multi-copy integration of pathway genes. The final a δ-tocotrienol titre in a 5 L bioreactor was 466.8 mg/L following fed-batchfermentation. This study represents the first successful de novo biosynthesis of δ-tocotrienol in Y. lipolytica, providing valuable insights into the synthesis of vitamin E-related compounds.

Resveratrol: A Narrative Review Regarding Its Mechanisms in Mitigating Obesity-Associated Metabolic Disorders

Resveratrol (RSV) is a naturally occurring astragalus-like polyphenolic compound with remarkable weight loss properties. However, the mechanism of RSV in treating obesity is unclear. In this narrative review, we explored electronic databases (PubMed) for research articles from 2021 to the present using the keywords "resveratrol" and "obesity". This article explores the mechanisms involved in the alleviation of obesity-related metabolic disorders by RSV. RSV affects obesity by modulating mitochondrial function, insulin signaling, and gut microbiota, regulating lipid metabolism, inhibiting oxidative stress, and regulating epigenetic regulation. Administering RSV to pregnant animals exhibits maternal and first-generation offspring benefits, and RSV administration to lactating animals has long-term benefits, which involve the epigenetic modulations by RSV. A comprehensive understanding of the epigenetic mechanisms of RSV regulation could help in developing drugs suitable for pregnancy preparation groups, pregnant women, and nursing infants.

Bioinformatics integration reveals key genes associated with mitophagy in myocardial ischemia-reperfusion injury

BACKGROUND

Myocardial ischemia is a prevalent cardiovascular disorder associated with significant morbidity and mortality. While prompt restoration of blood flow is essential for improving patient outcomes, the subsequent reperfusion process can result in myocardial ischemia-reperfusion injury (MIRI). Mitophagy, a specialized autophagic mechanism, has consistently been implicated in various cardiovascular disorders. However, the specific connection between ischemia-reperfusion and mitophagy remains elusive. This study aims to elucidate and validate central mitophagy-related genes associated with MIRI through comprehensive bioinformatics analysis.

METHODS

We acquired the microarray expression profile dataset (GSE108940) from the Gene Expression Omnibus (GEO) and identified differentially expressed genes (DEGs) using GEO2R. Subsequently, these DEGs were cross-referenced with the mitophagy database, and differential nucleotide sequence analysis was performed through enrichment analysis. Protein-protein interaction (PPI) network analysis was employed to identify hub genes, followed by clustering of these hub genes using cytoHubba and MCODE within Cytoscape software. Gene set enrichment analysis (GSEA) was conducted on central genes. Additionally, Western blotting, immunofluorescence, and quantitative polymerase chain reaction (qPCR) analyses were conducted to validate the expression patterns of pivotal genes in MIRI rat model and H9C2 cardiomyocytes.

RESULTS

A total of 2719 DEGs and 61 mitophagy-DEGs were identified, followed by enrichment analyses and the construction of a PPI network. HSP90AA1, RPS27A, EEF2, EIF4A1, EIF2S1, HIF-1α, and BNIP3 emerged as the seven hub genes identified by cytoHubba and MCODE of Cytoscape software. Functional clustering analysis of HIF-1α and BNIP3 yielded a score of 9.647, as determined by Cytoscape (MCODE). In our MIRI rat model, Western blot and immunofluorescence analyses confirmed a significant elevation in the expression of HIF-1α and BNIP3, accompanied by a notable increase in the ratio of LC3II to LC3I. Subsequently, qPCR confirmed a significant upregulation of HIF-1α, BNIP3, and LC3 mRNA in the MIRI group. Activation of the HIF-1α/BNIP3 pathway mediates the regulation of the degree of Mitophagy, thereby effectively reducing apoptosis in rat H9C2 cardiomyocytes.

CONCLUSIONS

This study has identified seven central genes among mitophagy-related DEGs that may play a pivotal role in MIRI, suggesting a correlation between the HIF-1α/BNIP3 pathway of mitophagy and the pathogenesis of MIRI. The findings highlight the potential importance of mitophagy in MIRI and provide valuable insights into underlying mechanisms and potential therapeutic targets for further exploration in future studies.

The Potential Role of Vitamin E and the Mechanism in the Prevention and Treatment of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) includes ulcerative colitis and Crohn's disease, and it is a multifactorial disease of the intestinal mucosa. Oxidative stress damage and inflammation are major risk factors for IBD. Vitamin E has powerful antioxidant and anti-inflammatory effects. Our previous work and other investigations have shown that vitamin E has a positive effect on the prevention and treatment of IBD. In this paper, the source and structure of vitamin E and the potential mechanism of vitamin E's role in IBD were summarized, and we also analyzed the status of vitamin E deficiency in patients with IBD and the effect of vitamin E supplementation on IBD. The potential mechanisms by which vitamin E plays a role in the prevention and treatment of IBD include improvement of oxidative damage, enhancement of immunity, maintenance of intestinal barrier integrity, and suppression of inflammatory cytokines, modulating the gut microbiota and other relevant factors. The review will improve our understanding of the complex mechanism by which vitamin E inhibits IBD, and it also provides references for doctors in clinical practice and researchers in this field.

Role of δ-tocotrienol and resveratrol supplementation in the regulation of micro RNAs in patients with metabolic syndrome: a randomized controlled trial

OBJECTIVE

To determine the effect of δ-tocotrienol and resveratrol mixture (TRM) supplementation in comparison to placebo for 24 weeks, on the relative expression of miRNAs (miRNA-130b-5p, miRNA-221-5p, miR-15b-5p, miRNA-122-5p, and miRNA-376b-5p) in patients with Metabolic syndrome (MetS).

DESIGN

This randomized placebo-controlled trial was conducted at the tertiary care institute of the NUMS, Rawalpindi, Pakistan. A total of 82 adult MetS patients were enrolled and randomly grouped into the TRM group (n=41) and the Placebo group (n=41). Patients in the TRM group were given 400mg capsules (δ-tocotrienol 250mg; Resveratrol 150mg) and placebo received (cellulose 400mg capsule) twice daily for 24 weeks.

RESULTS

The TRM supplementation revealed a significant (p<0.001) upregulation of 3.05-fold in miRNA-130b-5p and 2.45-fold in miRNA-221-5p while miRNA-122-5p was downregulated by 2.22-fold as compared to placebo. No significant difference was observed in miRNA-15b-5p and miRNA-376b-5p. Moreover, TRM group participants with reverted MetS had significantly (p<0.05) upregulated miRNA-130b-5p, miRNA-221-5p, and downregulated miRNA-122-5p relative to non-reverted patients with MetS.

CONCLUSION

Daily TRM supplementation may improve metabolic syndrome by upregulated miR-130b-5p, which is involved in central obesity and inflammation, as well as miR-221-5p, which is involved in insulin resistance. Additionally, TRM downregulate of miRNA 122, which improved dyslipidemia.

Tocotrienols: Exciting Biological and Pharmacological Properties of Tocotrienols and Naturally Occurring Compounds, Part II

δ-Tocotrienol plus AHA Step-1 diet in hypercholesterolemic subjects caused reductions in lipid parameters (14% to 18%) with 250 mg/d dose, and 500 mg/d resulted induction in these parameters. Although, α-tocopherol is the most bioavailable form of vitamin E. There are few reports on bioavailability of tocotrienols in humans. Pharmacokinetics and bioavailability of δ-tocotrienol was quantified on plasma levels of tocol isomers, cytokines, and microRNAs. Subjects were fed doses of 125 mg/d to 500 mg/d. Plasma samples collected between 0 h to 10 h, levels of tocols estimated by HPLC, which resulted dose-dependent increases in AUC0-10, Cmax0-∞, Tmaxh, t1/2h, Cl-T 1/h, Vd/f, keh-1. Maximum plasma levels of δ-tocotrienol were at 3 h (125 mg/d to 250 mg/d), 6 h (500 mg/d). Effects of 32 compounds were evaluated on TNF-α secretion, nitric oxide production, and gene expression (TNF-α, IL-1β, IL-6, iNOS activity) in PPAR-α knockout mice. Anticancer activities of thiostrepton, dexamethasone, 2-methoxyestradiol, δ-tocotrienol, quercetin, amiloride, quinine sulfate showed significant anti-proliferative properties in Hela cells, pancreatic, prostate, breast, lungs, melanoma, B-lymphocytes, T-cells (40% to 95%). Results of plasma total mRNAs after δ-tocotrienol feeding to hepatitis C patients revealed significant down-regulated gene expression of pro-inflammatory cytokines. A mixture of δ-tocotrienol, resveratrol, vitamin D3 (NS-3) were given two capsules/d or cellulose/olive oil as placebo to individuals with T2DM (24-weeks). Significant down-regulation (15% to 74%) of gene expression in diabetes biomarkers and decreases i n serum levels of fasting-glucose, HbA1c, hs-CRP, fasting-insulin, HOMA-IR, MDA (9% to 23%) were observed with NS-3 treated T2DM. Pure plasma mRNAs and miRNAs of pre-dose vs. post-dose of NS-3 treated samples were analyzed by Next Generation Sequencing (NGS). Venn diagrams have established genetic regulatory network images and canonical signaling pathways for mRNA, miRNA, and paired mRNA-miRNA.

Tocotrienol regulates osteoclastogenesis in rheumatoid arthritis

BACKGROUND/AIMS

The present study aimed to investigate whether tocotrienol regulates interleukin 17 (IL-17)-induced osteoclastogenesis in rheumatoid arthritis (RA).

METHODS

We evaluated the effect of tocotrienol on IL-17-induced receptor activator of nuclear factor kappa B ligand (RANKL) production using RA fibroblast-like synoviocyte (FLS), together with real-time polymerase chain reaction and enzyme-linked immunosorbent assay. Osteoclast differentiation was confirmed after culturing IL-17-treated RA FLS and Th17 cells with tocotrienol and monocytes. We analyzed the suppressive effect of tocotrienol on Th17 cells percentage or Th17-cytokine levels among peripheral blood mononuclear cells using flow cytometry.

RESULTS

We found that IL-17 stimulated FLS to produce RANKL and tocotrienol decreased this IL-17-induced RANKL production. Tocotrienol decreased the IL-17-induced activation of mammalian target of rapamycin, extracellular signal-regulated kinase, and inhibitor of kappa B-alpha. When monocytes were incubated with IL-17, RANKL, IL-17-treated FLS or Th17 cells, osteoclasts were differentiated and tocotrienol decreased this osteoclast differentiation. Tocotrienol reduced Th17 cell differentiation and the production of IL-17 and sRANKL; however, tocotrienol did not affect Treg cell differentiation.

CONCLUSION

Tocotrienol inhibited IL-17- activated RANKL production in RA FLS and IL-17-activated osteoclast formation. In addition, tocotrienol reduced Th17 differentiation. Therefore, tocotrienol could be a new therapeutic choice to treat bone destructive processes in RA.

De Novo High-Titer Production of Delta-Tocotrienol in Recombinant Saccharomyces cerevisiae

Delta-tocotrienol as a vitamin E isomer has received much attention because of its diverse biomedical applications. Microbial biosynthesis of delta-tocotrienol is a promising strategy for its economic and environmental advantages. Here, we accomplished complete biosynthesis of delta-tocotrienol in Saccharomyces cerevisiae from glucose. We first constructed and incorporated a heterologous pathway into the genome of S. cerevisiae by incorporating the genes hpd (from Pseudomonas putida KT2440), hpt (from Synechocystis sp. PCC 6803), and vte1 (from Arabidopsis thaliana) for the biosynthesis of delta-tocotrienol. We further enhanced the biosynthesis of the precursor geranylgeranyl diphosphate by overexpressing the thmg1 and ggppssa (from Sulfolobus acidocaldarius) genes, leading to a production titer of delta-tocotrienol of 1.39 ± 0.01 mg/L. Finally, we optimized the fermentation medium using the response surface methodology, enabling a high-titer production of delta-tocotrienol (3.56 ± 0.25 mg/L), ∼2.6-fold of that of the initial culture medium. Fed-batch fermentation in a 2 L fermenter was further used to enhance the production titer of delta-tocotrienol (4.10 ± 0.10 mg/L). To the best of our knowledge, this is the first report on the de novo biosynthesis of delta-tocotrienol in S. cerevisiae, and the highest titer obtained for microbial production of delta-tocotrienol.

Tocotrienols and Cancer: From the State of the Art to Promising Novel Patents

BACKGROUND

Tocotrienols (TTs) are vitamin E derivatives naturally occurring in several plants and vegetable oils. Like Tocopherols (TPs), they comprise four isoforms, α, β, γ and δ, but unlike TPs, they present an unsaturated isoprenoid chain. Recent studies indicate that TTs provide important health benefits, including neuroprotective, anti-inflammatory, anti-oxidant, cholesterol lowering and immunomodulatory effects. Moreover, they have been found to possess unique anti-cancer properties.

OBJECTIVE

The purpose of this review is to present an overview of the state of the art of TTs role in cancer prevention and treatment, as well as to describe recent patents proposing new methods for TTs isolation, chemical modification and use in cancer prevention and/or therapy.

METHODS

Recent literature and patents focusing on TTs anti-cancer applications have been identified and reviewed, with special regard to their scientific impact and novelty.

RESULTS

TTs have demonstrated significant anti-cancer activity in multiple tumor types, both in vitro and in vivo. Furthermore, they have shown synergistic effects when given in combination with standard anti-cancer agents or other anti-tumor natural compounds. Finally, new purification processes and transgenic sources have been designed in order to improve TTs production, and novel TTs formulations and synthetic derivatives have been developed to enhance their solubility and bioavailability.

CONCLUSION

The promising anti-cancer effects shown by TTs in several preclinical studies may open new opportunities for therapeutic interventions in different tumors. Thus, clinical trials aimed at confirming TTs chemopreventive and tumor-suppressing activity, particularly in combination with standard therapies, are urgently needed.