Investigating the Potential for Sulforaphane to Attenuate Gastrointestinal Dysfunction in mdx Dystrophic Mice

Anti-Inflammatory Therapeutic Mechanisms of Isothiocyanates: Insights from Sulforaphane

Isothiocyanates (ITCs) belong to a group of natural products that possess a highly reactive electrophilic -N=C=S functional group. They are stored in plants as precursor molecules, glucosinolates, which are processed by the tyrosinase enzyme upon plant tissue damage to release ITCs, along with other products. Isolated from broccoli, sulforaphane is by far the most studied antioxidant ITC, acting primarily through the induction of a transcription factor, the nuclear factor erythroid 2-related factor 2 (Nrf2), which upregulates downstream antioxidant genes/proteins. Paradoxically, sulforaphane, as a pro-oxidant compound, can also increase the levels of reactive oxygen species, a mechanism which is attributed to its anticancer effect. Beyond highlighting the common pro-oxidant and antioxidant effects of sulforaphane, the present paper was designed to assess the diverse anti-inflammatory mechanisms reported to date using a variety of in vitro and in vivo experimental models. Sulforaphane downregulates the expression of pro-inflammatory cytokines, chemokines, adhesion molecules, cycloxyhenase-2, and inducible nitric oxide synthase. The signalling pathways of nuclear factor κB, activator protein 1, sirtuins 1, silent information regulator sirtuin 1 and 3, and microRNAs are among those affected by sulforaphane. These anti-inflammatory actions are sometimes due to direct action via interaction with the sulfhydryl structural moiety of cysteine residues in enzymes/proteins. The following are among the topics discussed in this paper: paradoxical signalling pathways such as the immunosuppressant or immunostimulant mechanisms; crosstalk between the oxidative and inflammatory pathways; and effects dependent on health and disease states.

SFX-01 in hospitalised patients with community-acquired pneumonia during the COVID-19 pandemic: a double-blind, randomised, placebo-controlled trial

Introduction

Sulforaphane can induce the transcription factor, Nrf2, promoting antioxidant and anti-inflammatory responses. In this study, hospitalised patients with community-acquired pneumonia (CAP) were treated with stabilised synthetic sulforaphane (SFX-01) to evaluate impact on clinical status and inflammation.

Methods

Double-blind, randomised, placebo-controlled trial of SFX-01 (300 mg oral capsule, once daily for 14 days) conducted in Dundee, UK, between November 2020 and May 2021. Patients had radiologically confirmed CAP and CURB-65 (confusion, urea >7 mmol·L-1, respiratory rate ≥30 breaths·min-1, blood pressure <90 mmHg (systolic) or ≤60 mmHg (diastolic), age ≥65 years) score ≥1. The primary outcome was the seven-point World Health Organization clinical status scale at day 15. Secondary outcomes included time to clinical improvement, length of stay and mortality. Effects on Nrf2 activity and inflammation were evaluated on days 1, 8 and 15 by measurement of 45 serum cytokines and mRNA sequencing of peripheral blood leukocytes.

Results

The trial was terminated prematurely due to futility with 133 patients enrolled. 65 patients were randomised to SFX-01 treatment and 68 patients to placebo. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was the cause of CAP in 103 (77%) cases. SFX-01 treatment did not improve clinical status at day 15 (adjusted OR 0.87, 95% CI 0.41-1.83; p=0.71), time to clinical improvement (adjusted hazard ratio (aHR) 1.02, 95% CI 0.70-1.49), length of stay (aHR 0.84, 95% CI 0.56-1.26) or 28-day mortality (aHR 1.45, 95% CI 0.67-3.16). The expression of Nrf2 targets and pro-inflammatory genes, including interleukin (IL)-6, IL-1β and tumour necrosis factor-α, was not significantly changed by SFX-01 treatment. At days 8 and 15, respectively, 310 and 42 significant differentially expressed genes were identified between groups (false discovery rate adjusted p<0.05, log2FC >1).

Conclusion

SFX-01 treatment did not improve clinical status or modulate key Nrf2 targets in patients with CAP primarily due to SARS-CoV-2 infection.

MicroRNAs miR-584-5p and miR-425-3p Are Up-Regulated in Plasma of Colorectal Cancer (CRC) Patients: Targeting with Inhibitor Peptide Nucleic Acids Is Associated with Induction of Apoptosis in Colon Cancer Cell Lines

Liquid biopsy has dramatically changed cancer management in the last decade; however, despite the huge number of miRNA signatures available for diagnostic or prognostic purposes, it is still unclear if dysregulated miRNAs in the bloodstream could be used to develop miRNA-based therapeutic approaches. In one author's previous work, nine miRNAs were found to be dysregulated in early-stage colon cancer (CRC) patients by NGS analysis followed by RT-dd-PCR validation. In the present study, the biological effects of the targeting of the most relevant dysregulated miRNAs with anti-miRNA peptide nucleic acids (PNAs) were verified, and their anticancer activity in terms of apoptosis induction was evaluated. Our data demonstrate that targeting bloodstream up-regulated miRNAs using anti-miRNA PNAs leads to the down-regulation of target miRNAs associated with inhibition of the activation of the pro-apoptotic pathway in CRC cellular models. Moreover, very high percentages of apoptotic cells were found when the anti-miRNA PNAs were associated with other pro-apoptotic agents, such as sulforaphane (SFN). The presented data sustain the idea that the targeting of miRNAs up-regulated in the bloodstream with a known role in tumor pathology might be a tool for the design of protocols for anti-tumor therapy based on miRNA-targeting molecules.

p-TAK1 acts as a switch between myoblast proliferation phase and differentiation phase in mdx mice via regulating HO-1 expression

Skeletal muscle transforming growth factor-β-activated kinase 1 (TAK1) continuous excessive phosphorylation was observed in Duchenne muscular dystrophy (DMD) patients and mdx mice. Inhibiting TAK1 phosphorylation ameliorated fibrosis and muscular atrophy, while TAK1 knockout also impaired muscle regeneration. The definite effect and mechanism of p-TAK1 in muscle regeneration disorder is still obscure. In this study, BaCl₂-induced acute muscle injury model was used to investigate the role of p-TAK1 in myoblast proliferation and differentiation phase. The results showed that TAK1 phosphorylation was significantly up-regulated in proliferation phase along with Keap1/Nrf2/HO-1 signaling pathway activation, which was down-regulated in differentiation phase yet. In C2C12 cells, inhibiting TAK1 phosphorylation markedly suppressed the expression of heme oxygenase-1 (HO-1), and both myoblast proliferation and differentiation were inhibited. As for activation, p-TAK1 promoted myoblast proliferation via up-regulating HO-1 level. However, excessive TAK1 phosphorylation (induced by 20 ng·mL^-1 TGF-β1) notably up-regulated HO-1 expression, inhibiting myogenic differentiation antigen (MyOD) and myogenic differentiation. A mild p-TAK1 level (induced by 5 or 10 ng·mL^-1 TGF-β1) was beneficial for myoblast differentiation. In mdx mice, robust myoblast proliferation and differentiation arrest were observed with high p-TAK1 level in skeletal muscle. HO-1 expression was significantly up-regulated. TAK1 phosphorylation inhibitor NG25 (N-[4-[(4-ethylpiperazin-1-yl)methyl]-3-(trifluoromethyl)phenyl]-4-methyl-3-(1H-pyrrolo[2,3-b]pyridin-4-yloxy)benzamide) significantly inhibited HO-1 expression, relieved excessive myoblast proliferation and differentiation arrest, promoted new myofiber formation, and eventually improved muscle function. In conclusion, p-TAK1 acted as "a switch" between proliferation and differentiation phase. Mitigating p-TAK1 level transformed myoblast excessive proliferation phase into differentiation phase in mdx mouse via regulating HO-1 expression.