Role of Oxidative Stress and Nrf2/KEAP1 Signaling in Colorectal Cancer: Mechanisms and Therapeutic Perspectives with Phytochemicals

Repurposing celecoxib for colorectal cancer targeting via pH-triggered ultra-elastic nanovesicles: Pronounced efficacy through up-regulation of Wnt/β-catenin pathway in DMH-induced tumorigenesis

Celecoxib (CLX), a selective inhibitor for cyclooxygenase 2 (COX-2), has manifested potential activity against diverse types of cancer. However, low bioavailability and cardiovascular side effects remain the major challenges that limit its exploitation. In this work, we developed ultra-elastic nanovesicles (UENVs) with pH-triggered surface charge reversal traits that could efficiently deliver CLX to colorectal segments for snowballed tumor targeting. CLX-UENVs were fabricated via a thin-film hydration approach. The impact of formulation factors (Span 80, Tween 80, and sonication time) on the nanovesicular features was evaluated using Box-Behnken design, and the optimal formulation was computed. The optimum formulation was positively coated with polyethyleneimine (CLX-PEI-UENVs) and then coated with Eudragit S100 (CLX-ES-PEI-UENVs). The activity of the optimized nano-cargo was explored in 1,2-dimethylhydrazine-induced colorectal cancer in Wistar rats. Levels of COX-2, Wnt-2 and β-catenin were assessed in rats' colon. The diameter of the optimized CLX-ES-PEI-UENVs formulation was 253.62 nm, with a zeta potential of -23.24 mV, 85.64% entrapment, and 87.20% cumulative release (24 h). ES coating hindered the rapid release of CLX under acidic milieu (stomach and early small intestine) and showed extended release in the colon section. In colonic environments, the ES coating layer was removed due to high pH, and the charge on the nanovesicular corona was shifted from negative to positive. Besides, a pharmacokinetics study revealed that CLX-ES-PEI-UENVs had superior oral bioavailability by 2.13-fold compared with CLX suspension. Collectively, these findings implied that CLX-ES-PEI-UENVs could be a promising colorectal-targeted nanoplatform for effective tumor management through up-regulation of the Wnt/β-catenin pathway.

Dietary fiber as a wide pillar of colorectal cancer prevention and adjuvant therapy

Colorectal cancer is the third most incident and second most lethal type of cancer worldwide. Lifestyle and dietary patterns are the key factors for higher disease development risk. The dietary fiber intake from fruits and vegetables, mainly formed by food hydrocolloids, can help to lower the incidence of this type of neoplasia. Different food polysaccharides have applications in anti-tumoral therapy, such as coadjuvant to mainstream drugs, carriage-like properties, or direct influence on tumoral cells. Some classes include inulin, β-glucans, pectins, fucoidans, alginates, mucilages, and gums. Therefore, it is fundamental to discuss colorectal cancer mechanisms and the roles played by different polysaccharides in intestinal health. Genetic, environmental, and immunological modulation of mutated pathways regarding colorectal cancer has been explored before. Microbial diversity, byproduct formation (primarily short-chain fatty acids), inflammatory profile control, and tumoral mutated pathways regulation are thoroughly explored mechanisms by which dietary fiber sources influence a healthy gut ambiance.

A dual model of normal vs isogenic Nrf2-depleted murine epithelial cells to explore oxidative stress involvement

Cancer-derived cell lines are useful tools for studying cellular metabolism and xenobiotic toxicity, but they are not suitable for modeling the biological effects of food contaminants or natural biomolecules on healthy colonic epithelial cells in a normal genetic context. The toxicological properties of such compounds may rely on their oxidative properties. Therefore, it appears to be necessary to develop a dual-cell model in a normal genetic context that allows to define the importance of oxidative stress in the observed toxicity. Given that the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) is considered to be the master regulator of antioxidant defenses, our aim was to develop a cellular model comparing normal and Nrf2-depleted isogenic cells to qualify oxidative stress-related toxicity. We generated these cells by using the CRISPR/Cas9 technique. Whole-genome sequencing enabled us to confirm that our cell lines were free of cancer-related mutations. We used 4-hydroxy-2-nonenal (HNE), a lipid peroxidation product closely related to oxidative stress, as a model molecule. Here we report significant differences between the two cell lines in glutathione levels, gene regulation, and cell viability after HNE treatment. The results support the ability of our dual-cell model to study the role of oxidative stress in xenobiotic toxicity.

The Role of Vitamins in Mitigating the Effects of Various Stress Factors in Pigs Breeding

Good practices in farm animal care are crucial for upholding animal well-being, efficiency, and health. Pigs, like other farm animals, are exposed to various stressors, including environmental, nutritional, chemical, psychological, physiological, and metabolic stressors, which can disrupt their internal balance and compromise their well-being. Oxidative stress can adversely affect animal performance, fertility, and immunity, leading to economic losses for farmers. Dietary considerations are hugely important in attaining these objectives. This paper reviews studies investigating the impact of additional vitamin supplementation on stress reduction in pigs. Vitamin A can be beneficial in counteracting viral and parasitic threats. Vitamin B can be a potential solution for reproductive issues, but it might also be beneficial in reducing the effects of inappropriate nutrition. Vitamin C plays a vital role in reducing the effects of heat stress or exposure to toxins in pigs. Vitamin D proves to be beneficial in addressing stress induced mostly by infections and weaning, while vitamin E has been shown to mitigate the effects of toxins, heat stress, or transport stress. This review highlights the potential benefits of these dietary antioxidants in maintaining pig health, enhancing productivity, and counteracting the adverse effects of various stressors. Understanding the role of vitamins in pig nutrition and stress management is vital for optimising farm animal welfare and production efficiency.

Modulators of the Nrf2 Signaling Pathway Enhance the Cytotoxic Effect of Standard Chemotherapeutic Drugs on Organoids of Metastatic Colorectal Cancer

The activity of known modulators of the Nrf2 signaling pathway (bardoxolone and brusatol) was studied on cultures of tumor organoids of metastatic colorectal cancer previously obtained from three patients. The effect of modulators was studied both as monotherapy and in combination with standard chemotherapy drugs used to treat colorectal cancer. The Nrf2 inhibitor brusatol and the Nrf2 activator bardoxolone have antitumor activity. Moreover, bardoxolone and brusatol also significantly enhance the effect of the chemotherapy drugs 5-fluorouracil, oxaliplatin, and irinotecan metabolite SN-38. Thus, bardoxolone and brusatol can be considered promising candidates for further preclinical and clinical studies in the treatment of colorectal cancer.

Identification of novel Nrf2-activating neuroprotective agents: Elucidation of structural congeners of (-)-galiellalactone and congener-based novel Nrf2 activators

Herein, (-)-galiellalactone 1 congeners responsible for the nuclear factor erythroid 2-related factor 2 (Nrf2)-activating neuroprotective effects were elucidated. Additionally, novel congener-based Nrf2 activators were identified using a drug repositioning strategy. (-)-Galiellalactone, which comprises a tricyclic lactone skeleton, significantly activates antioxidant response element (ARE)-mediated transcription in neuroblastoma SH-SY5Y cells. Interestingly, two cyclohexene-truncated [3.3] bicyclic lactone analogs, which possess an exocyclic α-methylene-γ-butyrolactone moiety, exhibited higher Nrf2/ARE transcriptional activities than the parent (-)-galiellalactone. We confirmed that the cyclohexene moiety embedding the [3.3] bicyclic lactone congener does not play the essential role of (-)-galiellalactone for Nrf2/ARE activation. Nrf2/ARE activation by novel analogs resulted in the upregulation of downstream antioxidative and phase II detoxifying enzymes, heme oxygenase-1, and NAD(P)H quinone oxidoreductase 1, which are closely related to the cytoprotective effects on neurodegenerative diseases. (-)-Galiellalactone and its [3.3] bicyclic variants 3l and 3p increased the expression of antioxidant genes and exhibited neuroprotective effects against 6-hydroxydopamine-mediated neurotoxicity in the neuroblastoma SH-SY5Y cell line.

Triptolide inhibits proliferation and invasion of colorectal cancer cells by blocking Nrf2 expression

Triptolide (TPL), the main active ingredient of Tripterygium wilfordii, has anti-inflammatory, immunomodulatory, and antitumor actions. It can also inhibit cell proliferation and metastasis while promoting apoptosis of several tumors, such as colorectal cancer (CRC). However, the mechanism of TPL against CRC is not clear. This study was designed to investigate the effects and molecular mechanisms of TPL on the proliferation and invasion ability of CRC cells. A human CRC cell line (HT29 cell line) cultured in vitro was treated with different concentrations of TPL (0, 25, 50, and 100 nmol/L). The proliferation of cells was detected by MTT, the invasion ability of cells by Transwell, and the apoptosis level by flow cytometry. The protein expression levels of nuclear factor-erythroid 2-related factor 2 (Nrf2), matrix metalloproteinase (MMP)-2, and MMP-9 were detected by western blotting. After transfection with sh-Nrf2, HT29 cells were divided into NC group, NC + TPL group and sh-Nrf2 + TPL group, and the above assays were repeated for each group. TPL significantly inhibited the proliferation and invasion ability of HT29 cells and promoted apoptosis (p < .05). Notably, its inhibitory or promotional effects were concentration-dependent, which were enhanced with increasing drug concentration (p < .05). After silencing Nrf2 expression, the proliferation, and invasion ability of HT29 cells were further significantly inhibited while cells apoptosis was further promoted (p < .05). Besides, the decreased Nrf2 expression reduced the protein expression levels of MMP-2 and MMP-9 (p < .05). TPL can effectively inhibit the proliferation and invasion while promoting apoptosis of HT29 cells. And its mechanism of action may be related to the inhibition of Nrf2 signaling expression.

Multifunctional nanoparticle-mediated combining therapy for human diseases

Combining existing drug therapy is essential in developing new therapeutic agents in disease prevention and treatment. In preclinical investigations, combined effect of certain known drugs has been well established in treating extensive human diseases. Attributed to synergistic effects by targeting various disease pathways and advantages, such as reduced administration dose, decreased toxicity, and alleviated drug resistance, combinatorial treatment is now being pursued by delivering therapeutic agents to combat major clinical illnesses, such as cancer, atherosclerosis, pulmonary hypertension, myocarditis, rheumatoid arthritis, inflammatory bowel disease, metabolic disorders and neurodegenerative diseases. Combinatorial therapy involves combining or co-delivering two or more drugs for treating a specific disease. Nanoparticle (NP)-mediated drug delivery systems, i.e., liposomal NPs, polymeric NPs and nanocrystals, are of great interest in combinatorial therapy for a wide range of disorders due to targeted drug delivery, extended drug release, and higher drug stability to avoid rapid clearance at infected areas. This review summarizes various targets of diseases, preclinical or clinically approved drug combinations and the development of multifunctional NPs for combining therapy and emphasizes combinatorial therapeutic strategies based on drug delivery for treating severe clinical diseases. Ultimately, we discuss the challenging of developing NP-codelivery and translation and provide potential approaches to address the limitations. This review offers a comprehensive overview for recent cutting-edge and challenging in developing NP-mediated combination therapy for human diseases.

MiR-630 Promotes Radioresistance by Induction of Anti-Apoptotic Effect via Nrf2-GPX2 Molecular Axis in Head-Neck Cancer

Head and neck cancer (HNC) ranks among the top ten prevalent cancers worldwide. Radiotherapy stands as a pivotal treatment component for HNC; however, radioresistance in cancerous cells often leads to local recurrence, becoming a substantial factor in treatment failure. MicroRNAs (miRNAs) are compact, non-coding RNAs that regulate gene expression by targeting mRNAs to inhibit protein translation. Although several studies have indicated that the dysregulation of miRNAs is intricately linked with malignant transformation, understanding this molecular family's role in radioresistance remains limited. This study determined the role of miR-630 in regulating radiosensitivity in HNC. We discovered that miR-630 functions as an oncomiR, marked by its overexpression in HNC patients, correlating with a poorer prognosis. We further delineated the malignant function of miR-630 in HNC cells. While it had a minimal impact on cell growth, the miR-630 contributed to radioresistance in HNC cells. This result was supported by decreased cellular apoptosis and caspase enzyme activities. Moreover, miR-630 overexpression mitigated irradiation-induced DNA damage, evidenced by the reduced levels of the γ-H2AX histone protein, a marker for double-strand DNA breaks. Mechanistically, the overexpression of miR-630 decreased the cellular ROS levels and initiated Nrf2 transcriptional activity, resulting in the upregulation of the antioxidant enzyme GPX2. Thus, this study elucidates that miR-630 augments radioresistance by inducing an anti-apoptotic effect via the Nrf2-GPX2 molecular axis in HNC. The modulation of miR-630 may serve as a novel radiosensitizing target for HNC.

Exploring the potential of phenolic compounds from the coffee pulp in preventing cellular oxidative stress after in vitro digestion

The coffee pulp, a by-product of the coffee industry, contains a high concentration of phenolic compounds and caffeine. Simulated gastrointestinal digestion may influence these active compounds' bioaccessibility, bioavailability, and bioactivity. Understanding the impact of the digestive metabolism on the coffee pulp's phenolic composition and its effect on cellular oxidative stress biomarkers is essential. In this study, we evaluated the influence of in vitro gastrointestinal digestion of the coffee pulp flour (CPF) and extract (CPE) on their phenolic profile, radical scavenging capacity, cellular antioxidant activity, and cytoprotective properties in intestinal epithelial (IEC-6) and hepatic (HepG2) cells. The CPF and the CPE contained a high amount of caffeine and phenolic compounds, predominantly phenolic acids (3',4'-dihydroxycinnamoylquinic and 3,4-dihydroxybenzoic acids) and flavonoids (3,3',4',5,7-pentahydroxyflavone derivatives). Simulated digestion resulted in increased antioxidant capacity, and both the CPF and the CPE demonstrated free radical scavenging abilities even after in vitro digestion. The CPF and the CPE did not induce cytotoxicity in intestinal and hepatic cells, and both matrices exhibited the ability to scavenge intracellular reactive oxygen species. The coffee pulp treatments prevented the decrease of glutathione, thiol groups, and superoxide dismutase and catalase enzymatic activities evoked by tert-butyl hydroperoxide elicitation in IEC-6 and HepG2 cells. Our findings suggest that the coffee pulp could be used as a potent food ingredient for preventing cellular oxidative stress due to its high content of antioxidant compounds.

Ethanolic Extract of Polygonum minus Protects Differentiated Human Neuroblastoma Cells (SH-SY5Y) against H2O2-Induced Oxidative Stress

Neuronal models are an important tool in neuroscientific research. Hydrogen peroxide (H2O2), a major risk factor of neuronal oxidative stress, initiates a cascade of neuronal cell death. Polygonum minus Huds, known as 'kesum', is widely used in traditional medicine. P. minus has been reported to exhibit a few medicinal and pharmacological properties. The current study aimed to investigate the neuroprotective effects of P. minus ethanolic extract (PMEE) on H2O2-induced neurotoxicity in SH-SY5Y cells. LC-MS/MS revealed the presence of 28 metabolites in PMEE. Our study showed that the PMEE provided neuroprotection against H2O2-induced oxidative stress by activating the Nrf2/ARE, NF-κB/IκB and MAPK signaling pathways in PMEE pre-treated differentiated SH-SY5Y cells. Meanwhile, the acetylcholine (ACH) level was increased in the oxidative stress-induced treatment group after 4 h of exposure with H2O2. Molecular docking results with acetylcholinesterase (AChE) depicted that quercitrin showed the highest docking score at -9.5 kcal/mol followed by aloe-emodin, afzelin, and citreorosein at -9.4, -9.3 and -9.0 kcal/mol, respectively, compared to the other PMEE's identified compounds, which show lower docking scores. The results indicate that PMEE has neuroprotective effects on SH-SY5Y neuroblastoma cells in vitro. In conclusion, PMEE may aid in reducing oxidative stress as a preventative therapy for neurodegenerative diseases.

Phytochemicals targeting glycolysis in colorectal cancer therapy: effects and mechanisms of action

Colorectal cancer (CRC) is the third most common malignant tumor in the world, and it is prone to recurrence and metastasis during treatment. Aerobic glycolysis is one of the main characteristics of tumor cell metabolism in CRC. Tumor cells rely on glycolysis to rapidly consume glucose and to obtain more lactate and intermediate macromolecular products so as to maintain growth and proliferation. The regulation of the CRC glycolysis pathway is closely associated with several signal transduction pathways and transcription factors including phosphatidylinositol 3-kinases/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR), adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK), hypoxia-inducible factor-1 (HIF-1), myc, and p53. Targeting the glycolytic pathway has become one of the key research aspects in CRC therapy. Many phytochemicals were shown to exert anti-CRC activity by targeting the glycolytic pathway. Here, we review the effects and mechanisms of phytochemicals on CRC glycolytic pathways, providing a new method of drug development.

Modulation of NRF2/KEAP1-Mediated Oxidative Stress for Cancer Treatment by Natural Products Using Pharmacophore-Based Screening, Molecular Docking, and Molecular Dynamics Studies

Oxidative stress plays a significant role in the development of cancer. Inhibiting the protein-protein interaction (PPI) between Keap1 and Nrf2 offers a promising strategy to activate the Nrf2 antioxidant pathway, which is normally suppressed by the binding of Keap1 to Nrf2. This study aimed to identify natural compounds capable of targeting the kelch domain of KEAP1 using structure-based drug design methods. A pharmacophore model was constructed based on the KEAP1-inhibitor complex, leading to the selection of 6178 compounds that matched the model. Subsequently, docking and MM/GBSA analyses were conducted, resulting in the identification of 10 compounds with superior binding energies compared to the reference compound. From these, three compounds (ZINC000002123788, ZINC000002111341, and ZINC000002125904) were chosen for further investigation. Ligand-residue interaction analysis revealed specific interactions between these compounds and key residues, indicating their stability within the binding site. ADMET analysis confirmed that the selected compounds possessed desirable drug-like properties. Furthermore, molecular dynamics simulations were performed, demonstrating the stability of the ligand-protein complexes over a 100 ns duration. These findings underscore the potential of the selected natural compounds as agents targeting KEAP1 and provide valuable insights for future experimental studies.

Oxidative Stress, Inflammation and Colorectal Cancer: An Overview

Colorectal cancer (CRC) represents the second leading cause of cancer-related deaths worldwide. The pathogenesis of CRC is a complex multistep process. Among other factors, inflammation and oxidative stress (OS) have been reported to be involved in the initiation and development of CRC. Although OS plays a vital part in the life of all organisms, its long-term effects on the human body may be involved in the development of different chronic diseases, including cancer diseases. Chronic OS can lead to the oxidation of biomolecules (nucleic acids, lipids and proteins) or the activation of inflammatory signaling pathways, resulting in the activation of several transcription factors or the dysregulation of gene and protein expression followed by tumor initiation or cancer cell survival. In addition, it is well known that chronic intestinal diseases such as inflammatory bowel disease (IBD) are associated with an increased risk of cancer, and a link between OS and IBD initiation and progression has been reported. This review focuses on the role of oxidative stress as a causative agent of inflammation in colorectal cancer.

Molecular Docking Identifies 1,8-Cineole (Eucalyptol) as A Novel PPARγ Agonist That Alleviates Colon Inflammation

Inflammatory bowel disease, comprising Crohn's disease (CD) and ulcerative colitis (UC), is often debilitating. The disease etiology is multifactorial, involving genetic susceptibility, microbial dysregulation, abnormal immune activation, and environmental factors. Currently, available drug therapies are associated with adverse effects when used long-term. Therefore, the search for new drug candidates to treat IBD is imperative. The peroxisome proliferator-activated receptor-γ (PPARγ) is highly expressed in the colon. PPARγ plays a vital role in regulating colonic inflammation. 1,8-cineole, also known as eucalyptol, is a monoterpene oxide present in various aromatic plants which possess potent anti-inflammatory activity. Molecular docking and dynamics studies revealed that 1,8-cineole binds to PPARγ and if it were an agonist, that would explain the anti-inflammatory effects of 1,8-cineole. Therefore, we investigated the role of 1,8-cineole in colonic inflammation, using both in vivo and in vitro experimental approaches. Dextran sodium sulfate (DSS)-induced colitis was used as the in vivo model, and tumor necrosis factor-α (TNFα)-stimulated HT-29 cells as the in vitro model. 1,8-cineole treatment significantly decreased the inflammatory response in DSS-induced colitis mice. 1,8-cineole treatment also increased nuclear factor erythroid 2-related factor 2 (Nrf2) translocation into the nucleus to induce potent antioxidant effects. 1,8-cineole also increased colonic PPARγ protein expression. Similarly, 1,8-cineole decreased proinflammatory chemokine production and increased PPARγ protein expression in TNFα-stimulated HT-29 cells. 1,8-cineole also increased PPARγ promoter activity time-dependently. Because of its potent anti-inflammatory effects, 1,8-cineole may be valuable in treating IBD.

LncRNA MEG3 alleviates interstitial cystitis in rats by upregulating Nrf2 and inhibiting the p38/NF-κB pathway

PURPOSE

Interstitial cystitis (IC), a chronic pain syndrome characterized by urinary frequency, urgency, and bladder or pelvic floor pain, severely affects the quality of life of patients. The aim of this study was to investigate the role and mechanism of long noncoding RNA Maternally Expressed Gene3 (lncRNA MEG3) in IC.

METHODS

An IC rat model was established by intraperitoneal injection of cyclophosphamide combined with bladder perfusion of fisetin and tumor necrosis factor-α (TNF-α) to mimic IC. An in vitro model was established using TNF-α-induced rat bladder epithelium cells. H&E staining was used to assess bladder tissue damage and ELISA was used to measure inflammatory cytokine levels. Western blot analysis was used to examine Nrf2, Bax, Bcl-2, cleaved caspase-3, p-p38, p38, p-NF-κB and NF-κB protein expression levels. RNA immunoprecipitation and RNA pull-down assays were used to examine the interaction between MEG3 and Nrf2.

RESULTS

MEG3 levels were upregulated in IC tissues and bladder epithelial cells, whereas Nrf2 expression was found to be downregulated. Knockdown of MEG3 reduced bladder tissue injury, inflammation, oxidative stress and apoptosis. MEG3 was negatively correlated with Nrf2. Downregulation of MEG3 alleviated IC inflammation and injury by upregulating Nrf2 and inhibiting the p38/NF-κB pathway.

CONCLUSION

Downregulation of MEG3 alleviated inflammation and injury in IC rats by upregulating Nrf2 and inhibiting the p38/NF-κB pathway.

Carnosic Acid Ameliorates Indomethacin-Induced Gastric Ulceration in Rats by Alleviating Oxidative Stress and Inflammation

Nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin and indomethacin (IND) are the most commonly prescribed for inflammation or pain. However, widespread use causes several adverse effects, such as gastric ulcers, upper gastric system bleeding, and erosions. Carnosic acid (CA) is an important natural antioxidant found in rosemary (Rosmarinus essentials) and exhibits a protective effect by suppressing oxidative stress and inflammation. This study aimed to investigate the impact of CA on IND-induced gastric ulceration. Wistar male rats received CA (100 mg/kg) or esomeprazole (ESP) (20 mg/kg, standard drug) by oral gavage for 14 days, after that gastric ulceration was induced by oral administration of 100 mg/kg IND. CA pretreatment attenuated both gross morphological lesions and histopathological alterations. CA strongly reduced IND-induced oxidative stress, verified by a decrease in MDA (p < 0.001) and TOS levels (p < 0.05). Furthermore, an IND-dependent increase in CAT (p < 0.001) and GPx (p < 0.01) activities, as well as a reduction in GSH levels (p < 0.01), were ameliorated by CA pretreatment. CA also attenuated inflammatory damage by suppressing IL-1β (p < 0.01), IL-6 (p < 0.01), and TNFα (p < 0.001) production and increasing Nrf2/HO-1 (p < 0.05) expressions. In conclusion, CA shows a gastroprotective effect by reducing oxidative stress and attenuating inflammation.

Transient receptor potential channel stimulation induced oxidative stress and apoptosis in the colon of mice with colitis-associated colon cancer: modulator role of Sambucus ebulus L

BACKGROUND

Increased Ca²⁺ entry causes an increase in tumor cell proliferation, apoptosis, cytosolic reactive free oxygen species (cyROS), and mitochondrial ROS (miROS) in tumor cells. The cyROS and miROS stimulate the cation channels, including the TRPA1, TRPM2, and TRPV1. Sambucus ebulus L (SEB) (Dwarf Elder) induced both antioxidant and anticancer effects in the human hepatocarcinoma and human colon carcinoma cancer cell lines. We investigated the etiology of colorectal cancer and the impact of three channels, as well as the protective effects of SEB on apoptosis, cyROS, and miROS in the colon of mice with colitis-associated colon cancer (AOM/DSS).

METHODS

A total 28 mice were equally divided into four groups as control, SEB (100 mg/kg/day for 14 days), AOM/DSS, and SEB + AOM/DSS. Azoxymethane/dextran sulfate sodium-induced colon cancer associated with colitis was induced in the AOM/DSS groups within 10 weeks. At the end of the experiments, the colon samples were removed from the mice.

RESULTS

The protein bands of caspase - 3, TRPA1, TRPM2, and TRPV1 were increased by the treatments of AOM/DSS. The levels of apoptosis, cyROS, cleaved caspase - 3, and cleaved caspase - 9, as well as the depolarization of the mitochondrial membrane, all increased in the AOM/DSS group. Although they were reduced in the SEB and AOM/DSS + SEB groups by the treatments of SEB, TRPA1 (AP18), TRPM2 (ACA), and TRPV1 (capsazepine) antagonists, the apoptotic and oxidant values were further elevated in the AOM/DSS group by the treatments of TRPA1 (cinnamaldehyde), TRPM2 (H₂O₂), and TRPV1 (capsaicin) agonists.

CONCLUSION

The activations of TRPA1, TRPM2, and TRPV1 channels induced the increase of apoptotic and oxidant actions in the colon cancer cells, although their inhibition via SEB treatment decreased the actions. Hence, TRPA1, TRPM2, and TRPV1 activations could be used as effective agents in the treatment of colon tumors.

Establishment and external verification of an oxidative stress-related gene signature to predict clinical outcomes and therapeutic responses of colorectal cancer

Objective: Accumulated evidence highlights the biological significance of oxidative stress in tumorigenicity and progression of colorectal cancer (CRC). Our study aimed to establish a reliable oxidative stress-related signature to predict patients' clinical outcomes and therapeutic responses. Methods: Transcriptome profiles and clinical features of CRC patients were retrospectively analyzed from public datasets. LASSO analysis was used to construct an oxidative stress-related signature to predict overall survival, disease-free survival, disease-specific survival, and progression-free survival. Additionally, antitumor immunity, drug sensitivity, signaling pathways, and molecular subtypes were analyzed between different risk subsets through TIP, CIBERSORT, oncoPredict, etc. approaches. The genes in the signature were experimentally verified in the human colorectal mucosal cell line (FHC) along with CRC cell lines (SW-480 and HCT-116) through RT-qPCR or Western blot. Results: An oxidative stress-related signature was established, composed of ACOX1, CPT2, NAT2, NRG1, PPARGC1A, CDKN2A, CRYAB, NGFR, and UCN. The signature displayed an excellent capacity for survival prediction and was linked to worse clinicopathological features. Moreover, the signature correlated with antitumor immunity, drug sensitivity, and CRC-related pathways. Among molecular subtypes, the CSC subtype had the highest risk score. Experiments demonstrated that CDKN2A and UCN were up-regulated and ACOX1, CPT2, NAT2, NRG1, PPARGC1A, CRYAB, and NGFR were down-regulated in CRC than normal cells. In H₂O₂-induced CRC cells, their expression was notably altered. Conclusion: Altogether, our findings constructed an oxidative stress-related signature that can predict survival outcomes and therapeutic response in CRC patients, thus potentially assisting prognosis prediction and adjuvant therapy decisions.

New Insights Into the Anticancer Effects of p-Coumaric Acid: Focus on Colorectal Cancer

Colorectal cancer is considered the second most deadly cancer in the world. Studies have indicated that diet can prevent the risk of developing colorectal cancer. Recently, there has been an increasing interest in polyphenols due to their plausible effect on cancer prevention and treatment. p-Coumaric acid (p-CouA), a phenolic compound, is a cinnamic acid derivative found in several fruits, vegetables, and herbs. A growing body of evidence suggests that p-CouA may be an effective agent for preventing and managing colorectal cancer. In this current review, we briefly highlight the bioavailability of p-CouA. We also provide an up-to-date overview of molecular mechanisms underlying its anticancer effects, focusing on anti-inflammatory and antioxidant potentials, apoptosis induction, and cell cycle blockade. Finally, we discuss the impact of p-CouA on clonogenicity and multidrug resistance of colorectal cancer cells.

Multi-omics approach to study the dual effects of novel proteins on the intestinal health of juvenile largemouth bass (Micropterus salmoides) under an alternate feeding strategy

Introduction

In an effort to minimize the usage of fishmeal in aquaculture, novel protein diets, including Tenebrio molitor, cottonseed protein concentrate, Clostridium autoethanogenum, and Chlorella vulgaris were evaluated for their potential to replace fishmeal. Nevertheless, comprehensive examinations on the gut health of aquatic animals under an alternate feeding strategy when fed novel protein diets are vacant.

Methods

Five isonitrogenous and isolipidic diets containing various proteins were manufactured, with a diet consisting of whole fishmeal serving as the control and diets containing novel proteins serving as the experimental diets. Largemouth bass (Micropterus salmoides) with an initial body weight of 4.73 ± 0.04g employed as an experimental animal and given these five diets for the first 29 days followed by a fishmeal diet for the next 29 days.

Results

The results of this study demonstrated that the growth performance of novel protein diets in the second stage was better than in the first stage, even though only the C. vulgaris diet increased antioxidant capacity and the cottonseed protein concentrate diet decreased it. Concerning the intestinal barriers, the C. autoethanogenum diet lowered intestinal permeability and plasma IL-1β/TNF-α. In addition, the contents of intestinal immunological factors, namely LYS and sIgA-like, were greater in C. vulgaris than in fishmeal. From the data analysis of microbiome and metabolome, the levels of short chain fatty acids (SCFAs), anaerobic bacteria, Lactococcus, and Firmicutes were significantly higher in the C. autoethanogenum diet than in the whole fishmeal diet, while the abundance of Pseudomonas, aerobic bacteria, Streptococcus, and Proteobacteria was lowest. However, no extremely large differences in microbiota or short chain fatty acids were observed between the other novel protein diets and the whole fishmeal diet. In addition, the microbiota were strongly connected with intestinal SCFAs, lipase activity, and tight junctions, as shown by the Mantel test and Pearson's correlation.

Discussion

Taken together, according to Z-score, the ranking of advantageous functions among these protein diets was C. autoethanogenum diet > C. vulgaris diet > whole fishmeal diet > cottonseed protein concentrate > T. molitor diet. This study provides comprehensive data illustrating a mixed blessing effect of novel protein diets on the gut health of juvenile largemouth bass under an alternate feeding strategy.

Genistin modulates high-mobility group box protein 1 (HMGB1) and nuclear factor kappa-B (NF-κB) in Ehrlich-ascites-carcinoma-bearing mice

Cancer is the world's second-largest cause of death. Although there are numerous cancer treatment options, they are typically uncomfortable owing to side effects and ineffectual due to increased resistance to traditional anti-cancer medications or radiation therapy. A key method in cancer treatment is to target delayed/inhibited inflammation and apoptosis, which are very active areas of research. Natural chemicals originating from plants are of particular interest because of their high bioavailability, safety, few side effects, and, most importantly, cost-effectiveness. Flavonoids have become incredibly common as anti-cancer medications, with promising findings as cytotoxic anti-cancer agents that cause cancer cell death. Isolated compound (genistin) was evaluated for in vitro antiproliferative activity against breast cancer cell line (MCF-7 and MDA-MB-231). The compound exhibited good cytotoxic activities against both cell lines. In vivo antiproliferative efficacy was also investigated in Ehrlich's ascites carcinoma (EAC). Compared to the control group, genistin revealed a significant decrease in tumor weight, volume, high-mobility group box1 (HMGB1), and nuclear factor-kappa B (NF-κB) contents. On the other hand, B-cell lymphoma 2 (Bcl-2) contents increase suggesting an anti-inflammatory and anti-apoptotic activity through inhibition of HMGB1 signaling and activating the Bcl-2 pathway.

Oxidative Stress-Mediated Programmed Cell Death: a Potential Therapy Target for Atherosclerosis

Nowadays, as a type of orderly and active death determined by genes, programmed cell death (PCD), including apoptosis, pyroptosis, ferroptosis, and necroptosis, has attracted much attention owing to its participation in numerous chronic cardiovascular diseases, especially atherosclerosis (AS), a canonical chronic inflammatory disease featured by lipid metabolism disturbance. Abundant researches have reported that PCD under distinct internal conditions fulfills different roles of atherosclerotic pathological processes, including lipid core expansion, leukocyte adhesion, and infiltration. Noteworthy, emerging evidence recently has also suggested that oxidative stress (OS), an imbalance of antioxidants and oxygen free radicals, has the potential to mediate PCD occurrence via multiple ways, including oxidization and deubiquitination. Interestingly, more recently, several studies have proposed that the mediating mechanisms could effect on the atherosclerotic initiation and progression significantly from variable aspects, so it is of great clinical importance to clarify how OS-mediated PCD and AS interact. Herein, with the aim of summarizing potential and sufficient atherosclerotic therapy targets, we seek to provide extensive analysis of the specific regulatory mechanisms of PCD mediated by OS and their multifaceted effects on the entire pathological atherosclerotic progression.

Zinc Oxide Particles Can Cause Ovarian Toxicity by Oxidative Stress in Female Mice Model

Introduction

Zinc oxide nanoparticles (ZnO NPs) participate in all aspects of our lives, but with their wide application, more and more disadvantages are exposed. The goal of this study was to investigate the toxicity of ZnO NPs in female mice ovaries and explore its potential mechanism.

Methods

In this study, adult female mice were orally exposed to 0, 100, 200, and 400 mg/kg ZnO NPs for 7 days. We explored the underlying mechanisms via the intraperitoneal injection of N-acetyl-cysteine (NAC), an inhibitor of oxidative stress, and salubrinal (Sal), an inhibitor of endoplasmic reticulum (ER) stress.

Results

The results indicated that serum estradiol and progesterone levels declined greatly with increasing ZnO NPs dosage. Hematoxylin and eosin (HE) staining revealed increased atretic follicles and exfoliated follicular granulosa cells. Moreover, at the transcriptional level, antioxidant-related genes such as Keap1 and Nrf2, and ER stress-related genes PERK, eIF2α, and ATF4 were markedly upregulated. In addition, the expression of Caspase12, Caspase9, and Caspase3, which are genes related to apoptosis, was also upregulated in all ZnO NPs treatment groups. Serum malondialdehyde (MDA) content was remarkably up-regulated, whereas superoxide dismutase (SOD) activity was down-regulated. The 400 mg/kg ZnO NPs treatment group suffered the most substantial harm. However, ovarian damage was repaired when NAC and Sal were added to this group.

Conclusion

ZnO NPs had toxic effects on the ovary of female mice, which were due to oxidative stress, ER stress, and the eventual activation of apoptosis.

Regulation of Nrf2 and Nrf2-related proteins by ganoderma lucidum ın hepatocellular carcinoma

BACKGROUND

HCC is among the most common cancer. Ganoderma lucidum (G.lucidum) has been essential in preventing and treating cancer. The Nrf2 signaling cascade is a cell protective mechanism against further damage, such as cancer development. This signaling pathway upregulates the cytoprotective genes and is vital in eliminating xenobiotics and reactive oxygen. This study aimed to show the potential cytotoxic activity of G. lucidum aqueous extract in HCC.

METHODS AND RESULTS

MTT assay was used to detect cell viability. Nrf2-related proteins were measured by western blotting, and the flow cytometry method assayed cell population in different cycle phases. Cell viability was 49% and 47% following G. lucidum extract at 100 µg/ml at 24 and 48 h treatments, respectively. G. lucidum extract (aqueous, 100 or 50 µg/ml) treatments for 24, 48, or 72 h were able to significantly change the cytoplasmic/nuclear amount of Nrf2 and HO-1, NQO1 protein levels. Moreover, at both concentrations, arrest of the G0/G1 cell cycle was stimulated in HCC.

CONCLUSIONS

The activation of the Nrf2 signaling pathways seems to be among the mechanisms underlining the protective and therapeutic action of G. lucidum against HCC.

Transcription factor nuclear factor erythroid 2 p45-related factor 2 (NRF2) ameliorates sepsis-associated acute kidney injury by maintaining mitochondrial homeostasis and improving the mitochondrial function

Mitochondrial dysfunction has a role in sepsis-associated acute kidney injury (S-AKI), so the restoration of normal mitochondrial homeostasis may be an effective treatment strategy. Transcription factor nuclear factor erythroid 2 p45-related factor 2 (NRF2) is a main regulator of cell-redox homeostasis, and recent studies reported that NRF2 activation helped to preserve mitochondrial morphology and function under conditions of stress. However, the role of NRF2 in the process of S-AKI is still not well understood. The present study investigated whether NRF2 regulates mitochondrial homeostasis and influences mitochondrial function in S-AKI. We demonstrated activation of NRF2 in an in vitro model: lipopolysaccharide (LPS) challenge of ductal epithelial cells of rat renal tubules (NRK-52e cells), and an in vivo model: cecal ligation and puncture (CLP) of rats. Over-expression of NRF2 attenuated oxidative stress, apoptosis, and the inflammatory response; enhanced mitophagy and mitochondrial biogenesis; and mitigated mitochondrial damage in the in vitro model. In vivo experiments showed that rats treated with an NRF2 agonist had higher adenosine triphosphate (ATP) levels, lower blood urea nitrogen and creatinine levels, fewer renal histopathological changes, and higher expression of mitophagy-related proteins [PTEN-induced putative kinase 1 (PINK1), parkin RBR E3 ubiquitin protein ligase (PRKN), microtubule-associated protein 1 light chain 3 II (LC3 II)] and mitochondrial biogenesis-related proteins [peroxisome proliferator-activated receptor γ coactivator-1 (PGC-1α) and mitochondrial transcription factor A (TFAM)]. Electron microscopy of kidney tissues showed that mitochondrial damage was alleviated by treatment with an NRF2 agonist, and the opposite response occurred upon treatment with an NRF2 antagonist. Overall, our findings suggest that mitochondria have an important role in the pathogenesis of S-AKI, and that NRF2 activation restored mitochondrial homeostasis and function in the presence of this disease. This mitochondrial pathway has the potential to be a novel therapeutic target for the treatment of S-AKI.

Design, Synthesis, and In Vitro Evaluation of Novel 8-Amino-Quinoline Combined with Natural Antioxidant Acids

Overproduction of reactive oxygen species (ROS) and alterations in metallostasis are common and related hallmarks in several neurodegenerative diseases (NDDs). Nature-based derivatives always represent an attractive tool in MTDL drug design, especially against ROS in NDDs. On this notion, we designed a new series of 8-quinoline-N-substituted derivatives with a natural antioxidant portion (i.e., lipoic, caffeic, and ferulic acids). These compounds were shown to chelate copper, a metal involved in ROS-induced degeneration, and scavenger oxygen radicals in DPPH assay. Then, selected compounds 4 and 5 were evaluated in an in vitro model of oxidative stress and shown to possess cytoprotective effects in 661W photoreceptor-like cells. The obtained results may represent a starting point for the application of the proposed class of compounds in retinal neurodegenerative diseases such as retinitis pigmentosa (RP), comprising a group of hereditary rod–cone dystrophies that represent a major cause of blindness in patients of working age, where the progression of the disease is a multifactorial event, with oxidative stress contributing predominantly.

Targeting Nrf2-Mediated Oxidative Stress Response in Traumatic Brain Injury: Therapeutic Perspectives of Phytochemicals

Traumatic brain injury (TBI), known as mechanical damage to the brain, impairs the normal function of the brain seriously. Its clinical symptoms manifest as behavioral impairment, cognitive decline, communication difficulties, etc. The pathophysiological mechanisms of TBI are complex and involve inflammatory response, oxidative stress, mitochondrial dysfunction, blood-brain barrier (BBB) disruption, and so on. Among them, oxidative stress, one of the important mechanisms, occurs at the beginning and accompanies the whole process of TBI. Most importantly, excessive oxidative stress causes BBB disruption and brings injury to lipids, proteins, and DNA, leading to the generation of lipid peroxidation, damage of nuclear and mitochondrial DNA, neuronal apoptosis, and neuroinflammatory response. Transcription factor NF-E2 related factor 2 (Nrf2), a basic leucine zipper protein, plays an important role in the regulation of antioxidant proteins, such as oxygenase-1(HO-1), NAD(P)H Quinone Dehydrogenase 1 (NQO1), and glutathione peroxidase (GPx), to protect against oxidative stress, neuroinflammation, and neuronal apoptosis. Recently, emerging evidence indicated the knockout (KO) of Nrf2 aggravates the pathology of TBI, while the treatment of Nrf2 activators inhibits neuronal apoptosis and neuroinflammatory responses via reducing oxidative damage. Phytochemicals from fruits, vegetables, grains, and other medical herbs have been demonstrated to activate the Nrf2 signaling pathway and exert neuroprotective effects in TBI. In this review, we emphasized the contributive role of oxidative stress in the pathology of TBI and the protective mechanism of the Nrf2-mediated oxidative stress response for the treatment of TBI. In addition, we summarized the research advances of phytochemicals, including polyphenols, terpenoids, natural pigments, and otherwise, in the activation of Nrf2 signaling and their potential therapies for TBI. Although there is still limited clinical application evidence for these natural Nrf2 activators, we believe that the combinational use of phytochemicals such as Nrf2 activators with gene and stem cell therapy will be a promising therapeutic strategy for TBI in the future.

The Potential Role of Curcumin in Modulating the Master Antioxidant Pathway in Diabetic Hypoxia-Induced Complications

Oxidative stress is the leading player in the onset and development of various diseases. The Keap1-Nrf2 pathway is a pivotal antioxidant system that preserves the cells' redox balance. It decreases inflammation in which the nuclear trans-localization of Nrf2 as a transcription factor promotes various antioxidant responses in cells. Through some other directions and regulatory proteins, this pathway plays a fundamental role in preventing several diseases and reducing their complications. Regulation of the Nrf2 pathway occurs on transcriptional and post-transcriptional levels, and these regulations play a significant role in its activity. There is a subtle correlation between the Nrf2 pathway and the pivotal signaling pathways, including PI3 kinase/AKT/mTOR, NF-κB and HIF-1 factors. This demonstrates its role in the development of various diseases. Curcumin is a yellow polyphenolic compound from Curcuma longa with multiple bioactivities, including antioxidant, anti-inflammatory, anti-tumor, and anti-viral activities. Since hyperglycemia and increased reactive oxygen species (ROS) are the leading causes of common diabetic complications, reducing the generation of ROS can be a fundamental approach to dealing with these complications. Curcumin can be considered a potential treatment option by creating an efficient therapeutic to counteract ROS and reduce its detrimental effects. This review discusses Nrf2 pathway regulation at different levels and its correlation with other important pathways and proteins in the cell involved in the progression of diabetic complications and targeting these pathways by curcumin.

Antioxidant and antiproliferative potential of ethanolic extracts from Moringa oleifera, Tropaeolum tuberosum and Annona cherimola in colorrectal cancer cells

Moringa oleifera, Tropaeolum tuberosum and Annona cherimola are medicinal plants traditionally used in Ecuador. However, their therapeutic properties are not completely known. We analyzed chromatographically ethanolic extracts of the seeds of M. oleifera, A. cherimola and the tubers of T. tuberosum; all presented a high content of polyphenols. The extract of A. cherimola showed the highest antioxidant activity and M. oleifera had the highest capacity to enhance the activity of detoxifying enzymes such as glutathione S-transferase and quinone oxidoreductase. The antitumor effect of these extracts was evaluated in vitro with colorectal cancer (CRC) cell lines T84, HCT-15, SW480 and HT-29, as well as with cancer stem cells (CSCs). A. cherimola and M. oleifera extracts presented the lowest IC₅₀ in T-84 and HCT-15 (resistant) cells, respectively, as well as the highest level of inhibition of proliferation in multicellular tumor spheroids of HCT-15 cells. The inhibitory effect on CSCs is noteworthy because in vivo, these cells are often responsible for cancer recurrences and resistance to chemotherapy. Moreover, all extracts showed a synergistic activity with 5-Fu. The antiproliferative mechanism of the extracts was related to overexpression of caspases 9, 8 and 3 and increased production of reactive oxygen species. In addition, we observed cell death by autophagy in M. oleifera and T. tuberosum extracts. Therefore, these ethanolic extracts are excellent candidates for future molecular analysis of the presence of bioactive compounds and in vivo studies which could improve colon cancer therapy.

Comparative Analysis of Phenolic Composition of Six Commercially Available Chamomile (Matricaria chamomilla L.) Extracts: Potential Biological Implications

Several phytochemical-containing herbal extracts are increasingly marketed as health-promoting products. In particular, chamomile (Matricaria recutita L.) is well known for its anti-inflammatory, analgesic, and antitumor properties. Here, we evaluated differences in chemical composition among six commercially available products and their potential impact on biological activity in human immortalized colonocytes. Our investigation encompassed: (i) preparation of dry extracts and yield evaluation; (ii) qualitative and quantitative analysis of phenol content; (iii) modulation of redox state; and (iv) bioavailability of main bioactive compounds. We demonstrated that apparently identical products showed huge heterogeneity, in terms of yield extraction, chemical composition, and antioxidant effects. All samples contained high amounts of flavonoids and cinnamic acid derivatives, but differentially concentrated in the six extracts. Depending on polyphenol content, chamomile samples possessed variable antioxidant potential, in terms of decreased radical generation and increased reduced glutathione levels. The observed effects might be ascribed to flavones (apigenin, luteolin, and their glycones) highly represented in the six extracts. Nonetheless, chamomile extracts exerted cytotoxic effects at high concentrations, suggesting that a herbal medicine is not always safe. In conclusion, due to the complexity and variability of plant matrices, studies evaluating effectiveness of chamomile should always be accompanied by preliminary characterization of phytochemical composition.

Anti-Inflammatory and Anticancer Effects of Microalgal Carotenoids

Acute inflammation is a key component of the immune system’s response to pathogens, toxic agents, or tissue injury, involving the stimulation of defense mechanisms aimed to removing pathogenic factors and restoring tissue homeostasis. However, uncontrolled acute inflammatory response may lead to chronic inflammation, which is involved in the development of many diseases, including cancer. Nowadays, the need to find new potential therapeutic compounds has raised the worldwide scientific interest to study the marine environment. Specifically, microalgae are considered rich sources of bioactive molecules, such as carotenoids, which are natural isoprenoid pigments with important beneficial effects for health due to their biological activities. Carotenoids are essential nutrients for mammals, but they are unable to synthesize them; instead, a dietary intake of these compounds is required. Carotenoids are classified as carotenes (hydrocarbon carotenoids), such as α- and β-carotene, and xanthophylls (oxygenate derivatives) including zeaxanthin, astaxanthin, fucoxanthin, lutein, α- and β-cryptoxanthin, and canthaxanthin. This review summarizes the present up-to-date knowledge of the anti-inflammatory and anticancer activities of microalgal carotenoids both in vitro and in vivo, as well as the latest status of human studies for their potential use in prevention and treatment of inflammatory diseases and cancer.

An Update on the Role of Nrf2 in Respiratory Disease: Molecular Mechanisms and Therapeutic Approaches

Nuclear factor erythroid 2-related factor (Nrf2) is a transcriptional activator of the cell protection gene that binds to the antioxidant response element (ARE). Therefore, Nrf2 protects cells and tissues from oxidative stress. Normally, Kelch-like ECH-associated protein 1 (Keap1) inhibits the activation of Nrf2 by binding to Nrf2 and contributes to Nrf2 break down by ubiquitin proteasomes. In moderate oxidative stress, Keap1 is inhibited, allowing Nrf2 to be translocated to the nucleus, which acts as an antioxidant. However, under unusually severe oxidative stress, the Keap1-Nrf2 mechanism becomes disrupted and results in cell and tissue damage. Oxide-containing atmospheric environment generally contributes to the development of respiratory diseases, possibly leading to the failure of the Keap1-Nrf2 pathway. Until now, several studies have identified changes in Keap1-Nrf2 signaling in models of respiratory diseases, such as acute respiratory distress syndrome (ARDS)/acute lung injury (ALI), chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), and asthma. These studies have confirmed that several Nrf2 activators can alleviate symptoms of respiratory diseases. Thus, this review describes how the expression of Keap1-Nrf2 functions in different respiratory diseases and explains the protective effects of reversing this expression.