Myricetin Abrogates Cisplatin-Induced Oxidative Stress, Inflammatory Response, and Goblet Cell Disintegration in Colon of Wistar Rats

Myricetin ameliorates cognitive impairment in 3×Tg Alzheimer's disease mice by regulating oxidative stress and tau hyperphosphorylation

BACKGROUND

Alzheimer's disease is characterized by abnormal β-amyloid (Aβ) plaque accumulation, tau hyperphosphorylation, reactive oxidative stress, mitochondrial dysfunction and synaptic loss. Myricetin, a dietary flavonoid, has been shown to exert neuroprotective effects in vitro and in vivo. Here, we aimed to elucidate the mechanism and pathways involved in the protective effect of myricetin.

METHODS

The effect of myricetin was assessed on Aβ42 oligomer-treated neuronal SH-SY5Y cells and in 3×Tg mice. Behavioral tests were performed to assess the cognitive effects of myricetin (14 days, ip) in 3×Tg mice. The levels of beta-amyloid precursor protein (APP), synaptic and mitochondrial proteins, glycogen synthase kinase3β (GSK3β) and extracellular regulated kinase (ERK) 2 were assessed via Western blotting. Flow cytometry assays, immunofluorescence staining, and transmission electron microscopy were used to assess mitochondrial dysfunction and reactive oxidative stress.

RESULTS

We found that, compared with control treatment, myricetin treatment improved spatial cognition and learning and memory in 3×Tg mice. Myricetin ameliorated tau phosphorylation and the reduction in pre- and postsynaptic proteins in Aβ42 oligomer-treated neuronal SH-SY5Y cells and in 3×Tg mice. In addition, myricetin reduced reactive oxygen species generation, lipid peroxidation, and DNA oxidation, and rescued mitochondrial dysfunction via the associated GSK3β and ERK 2 signalling pathways.

CONCLUSIONS

This study provides new insight into the neuroprotective mechanism of myricetin in vitro in cell culture and in vivo in a mouse model of Alzheimer's disease.

Unveiling myricetin's pharmacological potency: A comprehensive exploration of the molecular pathways with special focus on PI3K/AKT and Nrf2 signaling

Myricetin can be found in the traditional Chinese medicinal plant, Myrica rubra. Myricetin is a flavonoid that is present in many vegetables, fruits, and plants and is considered to have strong antioxidant properties as well as a wide range of therapeutic applications. Growing interest has been piqued by its classification as a polyphenolic molecule because of its potential therapeutic benefits in both the prevention and management of numerous medical conditions. To clarify myricetin's traditional medical uses, modern research has investigated various pharmacological effects such as antioxidant, anticancer, anti-inflammation, antiviral, antidiabetic, immunomodulation, and antineurodegenerative effects. Myricetin shows promise as a nutritional flavonol that could be beneficial in the prevention and mitigation of prevalent health conditions like diabetes, cognitive decline, and various types of cancer in humans. The findings included in this study indicate that myricetin has a great deal of promise for application in the formulation of medicinal products and nutritional supplements since it affects several enzyme activities and alters inflammatory markers. However, comprehensive preclinical studies and research studies are necessary to lay the groundwork for assessing myricetin's possible effectiveness in treating these long-term ailments. This review summarizes both in vivo and in vitro studies investigating myricetin's possible interactions through the nuclear factor-E2-related factor 2 (Nrf2) as well as PI3K (phosphatidylinositol 3-kinase)/AKT (protein kinase B) signaling pathways in an attempt to clarify the compound's possible clinical applicability across a range of disorders.

Anti-inflammatory natural products modulate interleukins and their related signaling markers in inflammatory bowel disease: A systematic review

This review aims to identify in vivo studies investigating the potential of plant substances and their natural molecules in managing inflammatory bowel disease (IBD). Specifically, the objective is to examine the impact of these substances on interleukins and other key inflammatory signaling markers. Relevant articles published up to December 2022 were identified through a search of the PubMed, Scopus, Web of Science, and Embase databases. The search used keywords including "inflammatory bowel disease", "medicinal plants", "natural molecules", "anti-inflammatory", and "ulcerative colitis", and identified 1,878 potentially relevant articles, of which 89 were included in this review after completion of the selection process. This study provides preclinical data on natural products (NPs) that can potentially treat IBD, including ulcerative colitis. The main actions of these NPs relate to their effects on nuclear factor kappa B (NF-κB), the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway, the regulation of T helper 17/regulatory T cells balance, and oxidative stress. The ability of these NPs to inhibit intestinal inflammation appears to be dependent on lowering levels of the pro-inflammatory cytokines tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β, and IL-17, via the Jun N-terminal kinase (JNK)1, NF-κβ-p65, and STAT3 pathways. In addition, NPs were shown to reduce oxidative stress and the severity of ulcerative colitis, as well as increase the activity of antioxidant enzymes. These actions suggest that NPs represent a promising treatment for IBD, and potentially have greater efficacy and safety than current treatments.

Hepatoprotective role of myricitrin isolated from Mimusops elengi Linn. leaves extract on γ-radiation-induced liver damage in rats: Phyto-biochemical investigations

The hepatoprotective effects of methanol extract of Mimusops elengi Linn. (M. elengi L.) leaves and isolated pure myricitrin (3-, 4-, 5-, 5, 7-five hydroxyflavone-3-O-α-l-rhamnoside) (Myr) were evaluated in male rats exposed to γ-irradiation. The extraction of M. elengi L. leaves was performed using ethyl acetate (EtOAC). Seven groups of rats were used: control group, irradiated (IRR) group (6 Gy of γ-rays in a single dose), vehicle group (oral administration of 0.5% carboxymethyl cellulose for 10 days), EtOAC extract group (100 mg/kg body weight of extract, orally for 10 days), EtOAC + IRR group (administration of extract and exposure to γ-rays on Day 7), Myr group (50 mg/kg body weight Myr, orally for 10 days), and Myr + IRR group (administration of Myr and exposure to γ-rays on Day 7). High-performance liquid chromatography and 1H-nuclear magnetic resonance were used to isolate and characterize the compounds from M. elengi L. leaves. Enzyme-linked immunosorbent assay was used for biochemical analyses. Identified compounds were Myr, myricetin 3-O-galactoside, myricetin 3-O-rahmnopyranoside (1 → 6) glucopyranoside, quercetin, quercitol, gallic acid, α-,β-amyrin, ursolic acid, and lupeol. Serum aspartate transaminase and alanine transaminase activities were significantly increased, while serum protein and albumin levels were significantly decreased after irradiation. Hepatic levels of tumor necrosis factor-α, prostaglandin 2, inducible nitric oxide synthase, interleukin-6 (IL-6), and IL-12 were increased following irradiation. Improvements were observed in most serological parameters after treatment with extract or pure Myr, with histological analyses confirming decreased liver injury in treated rats. Our study demonstrates that pure Myr has a greater hepatoprotective effect than M. elengi leaf extracts against irradiation-induced hepatic inflammation.

The antioxidant effect of Aronia melanocarpa extract in rats oxidative stress induced by cisplatin administration

BACKGROUND

The reactive oxygen species generated by numerous xenobiotic substances has as consequences the impairment of different organs normal function. Many plants pose antioxidant activity to counteract oxidative stress, among them being the chokeberry (Aronia melanocarpa). The purpose of present study was to determine if the use of A. melanocarpa extract can counteract the oxidative stress induced by cisplatin administration in rats.

MATERIAL AND METHODS

The study was made on forty Wistar rats divided in four groups as follows: C (control): receiving i.p. 1 mL of saline solution; E1: receiving cisplatin 20 mg/kg bw, i.p.; E2: receiving cisplatin 20 mg/kg bw, i.p and A. melanocarpa berry 6 % aqueous extract as drinking water, and CB (control blank): i.p 1 mL saline solution and A. melanocarpa 6 % aqueous extract for four weeks.

RESULTS

Administration of Cisplatin was followed by the increase of serum superoxide dismutase (+21.18 %, P < 0.05), catalase (+25.44 %, P < 0.001), glutathione peroxidase (+17.88 %, P < 0.05) and thiobarbituric reactive substances (+28.17 %, P < 0.01) but significantly decreased glutathione reductase (-22.35 %, P < 0.001) level comparative to control, pointing out that administration of cisplatin induced oxidative stress in rats. In groups that received A. melanocarpa extract as drinking water, we noted that the levels of the oxidative stress biomarkers tended to be restored almost to normal levels, which could be a possible good antioxidant used in condition to cisplatin use. Also, we noted a significant (P < 0.001) decrease of total antioxidant capacity in liver and kidney of rats exposed to cisplatin, recovered in those that received chokeberry. Studied trace elements important for the stress oxidative enzymes (Cu, Zn, Fe and Mn) were decreased in cisplatin exposed groups compared to control and mainly all were almost to normal level in groups receiving A. melanocarpa.

CONCLUSION

A. melanocarpa extract due to its antioxidants content could offer protection against free radicals produced as a consequence of cisplatin use.

Dietary myricetin assuages atrazine-mediated hypothalamic-pituitary-testicular axis dysfunction in rats

Atrazine (ATZ) exposure is associated with reproductive dysfunction in both animals and humans. Myricetin, a flavonoid compound, is well documented for its numerous pharmacological activities. However, the impact of myricetin on the atrazine-mediated dysfunctional hypothalamic-pituitary-testicular axis is not known. This study investigated the role of myricetin on the atrazine-induced alterations in the male reproductive axis in rats orally gavaged with ATZ alone (50 mg/kg) or co-treated with ATZ + myricetin (MYR) at 5, 10, and 20 mg/kg for 30 consecutive days. Myricetin assuaged ATZ-induced reductions in intra-testicular testosterone, serum follicle-stimulating hormone, luteinizing hormone, and testosterone, coupled with decreases in alkaline phosphatase, acid phosphatase, lactate dehydrogenase, and glucose-6-phosphate dehydrogenase activities. Also, MYR treatment improved epididymal sperm count and motility and decreased sperm defects in ATZ-treated rats. Testicular sperm number, daily sperm production, and sperm viability remained unchanged in all treatment groups. Administration of MYR abated ATZ-mediated depletion in antioxidant status, an increase in myeloperoxidase activity, nitric oxide, hydrogen peroxide, malondialdehyde levels, and reactive oxygen and nitrogen species, as well as the histological lesions in the hypothalamus, epididymis, and testes of treated animals. All in all, MYR mitigated atrazine-mediated functional changes in the reproductive axis via anti-inflammatory and antioxidant mechanisms in atrazine-exposed rats. Dietary intake of MYR could be a worthy chemoprotective approach against reproductive dysfunction related to ATZ exposure.

Bromelain protects against cisplatin-induced ocular toxicity through mitigating oxidative stress and inflammation

The aim of this study was to investigate the molecular, biochemical, and histopathological effects of bromelain, which has antioxidant and anti-inflammatory properties, against cisplatin-induced ocular toxicity. The groups were designed as (1) Control, (2) Cisplatin (7 mg/kg, intraperitoneally), (3) Cisplatin + Bromelain (50 mg/kg, orally for 14 consecutive days), (4) Cisplatin + Bromelain (100 mg/kg, orally for 14 consecutive days). The activity of total antioxidant capacity (TAC) and total oxidant status (TOS) and levels of reactive oxygen species (ROS), superoxide dismutase (SOD), malondialdehyde (MDA), interleukin-1β (IL-1β), IL-10, nuclear factor kappa B (NF-κB), tumor necrosis factor-alpha (TNF-α) and 8-OHdG were measured in ocular tissue. The mRNA expression of NF-κB and Caspase-3 was also evaluated. Also, ocular sections were evaluated histopathologically. Bromelain demonstrated a dose-dependent protective effect in cisplatin-induced toxicity by regulating oxidative stress, inflammation, and tissue damage. Our results suggested that bromelain may be a potential adjuvant that can protect the eye from cisplatin-induced toxicity.

Numerical modelling of WNT/β-catenin signal pathway in characterization of EMT of colorectal carcinoma cell lines after treatment with Pt(IV) complexes

BACKGROUND AND OBJECTIVE

Colorectal cancer (CRC) is at the top of the most common cancer types in the world, with significant mortality rates among both men and women. Deregulation of Wnt/β-catenin pathway and cell-cell junctions' components, acquisition of invasive phenotype, epithelial-mesenchymal transition (EMT) and invasion are important for development and progression of colorectal cancer. Numerical simulation presents method for estimation of the Wnt pathway via its individual components in cells, thus providing information about EMT, migratory and invasive potential. By using this numerical model, the effectiveness of treatment in EMT suppression can be assessed. Furthermore, the model can be adapted to ``every'' cell type, application time or duration of treatment can be also modified.

METHODS

We characterized colorectal cancer (CRC) cell lines (HCT-116, SW-480) from the aspect of EMT, via markers β-catenin and E-cadherin using numerical modeling. To confirm the numerical model, cells were treated with sublethal concentrations of platinum(IV) complexes and their ligands. We confirmed β-catenin regulated expression of mesenchymal markers: N-cadherin, Vimentin and MMP-9, and decreased E-cadherin expression. Treatment-induced changes were determined in the protein expression of tested markers and results showed cell-specific responses. Molecular docking was performed to investigate exact effects of treatments on E-cadherin and β-catenin in cell-cell junctions and individually in tested cells.

RESULTS

The application of the numerical model via β-catenin and E-cadherin (experimentally measured), is largely valid for the categorization of EMT progression in cells. This numerical modeling better characterizes cells with single cell migration, higher expression of mesenchymal markers, and advanced mesenchymal phenotype like HCT-116 cell line. The model was validated for the treatments and results show HCT-116 cells as more sensitive to applied compounds, among which ligands were more potent in reducing migration and invasiveness. Anti-migratory/invasive effects were due to increased E-cadherin, cytoplasmic β-catenin expression and suppressed mesenchymal markers. In silico methods showed higher affinity of tested chemicals towards free β-catenin, which is the key for regulation of migratory/invasive potential.

CONCLUSIONS

Our study shows that, no matter individual properties of cell lines and EMT degree, de novo formation of intercellular junctions stands in the basis of anti-migratory/invasive process.

A Comprehensive Review of Natural Compounds for Wound Healing: Targeting Bioactivity Perspective

Wound healing is a recovering process of damaged tissues by replacing dysfunctional injured cellular structures. Natural compounds for wound treatment have been widely used for centuries. Numerous published works provided reviews of natural compounds for wound healing applications, which separated the approaches based on different categories such as characteristics, bioactivities, and modes of action. However, current studies provide reviews of natural compounds that originated from only plants or animals. In this work, we provide a comprehensive review of natural compounds sourced from both plants and animals that target the different bioactivities of healing to promote wound resolution. The compounds were classified into four main groups (i.e., anti-inflammation, anti-oxidant, anti-bacterial, and collagen promotion), mostly studied in current literature from 1992 to 2022. Those compounds are listed in tables for readers to search for their origin, bioactivity, and targeting phases in wound healing. We also reviewed the trend in using natural compounds for wound healing.

The Mechanistic Perspective of Bilobetin Protective Effects against Cisplatin-Induced Testicular Toxicity: Role of Nrf-2/Keap-1 Signaling, Inflammation and Apoptosis

Cisplatin (CP) is a productive anti-tumor used to treat numerous tumors. However, multiple toxicities discourage prolonged use, especially toxicity on the reproductive system. This experiment was mapped out to determine the potential therapeutic impact of Bilobetin on CP-induced testicular damage. Herein, Bilobetin was isolated from Cycas thouarsii leaves R. Br ethyl acetate fractions for the first time. A single dose of CP (7 mg/kg, IP) was used to evoke testicular toxicity on the third day. Rats were classified into five groups; Normal control, Bilobetin 12 mg/kg, Untreated CP, and CP treated with Bilobetin (6 and 12 mg/kg, respectively) orally daily for ten days. Bilobetin treatment ameliorated testicular injury. In addition, it boosted serum testosterone levels considerably and restored relative testicular weight. Nevertheless, apoptosis biomarkers such as P53, Cytochrome-C, and caspase-3 decreased significantly. Additionally, it enhanced the testes’ antioxidant status via the activation of Nrf-2, inhibition of Keap-1, and significant elevation of SOD activity in addition to a reduction in lipid peroxidation. Histopathologically, Bilobetin preserved testicular architecture and improved testicular immunostaining of Ki67 substantially, showing evidence of testicular regeneration. Bilobetin’s beneficial effects on CP-induced testicular damage are associated with enhanced antioxidant effects, lowered apoptotic signals, and the restoration of testes’ regenerative capability. In addition, Bilobetin may be used in combination with CP in treatment protocols to mitigate CP-induced testicular injury.

Melatonin is effective in attenuating cisplatin-induced neurotoxicity

Cisplatin (Cis) is a chemotherapeutic agent that has many side effects. Neurotoxicity is one of the most important of these side effects. Oxidative stress and neuroinflammation are the best-known mechanisms in the pathogenesis of neurotoxicity development. In this study, we aimed to determine whether melatonin (Mel), with antioxidant and anti-inflammatory effects, is effective in preventing Cis-induced neurotoxicity. Forty-eight male Sprague-Dawley rats were divided into six groups (n = 8) as follows: control (0.9% NaCl), vehicle (5% ethanol), Cis (6 mg/kg), Cis (6 mg/kg) + vehicle (5% ethanol), Mel (20 mg/kg), and Cis (6 mg/kg) + Mel (20 mg/kg) groups. Cis was administered as a single dose on the 3rd day of the experiment while Mel was given for 5 days. All administrations were performed via intraperitoneal injection. After injections, T-maze, rotarod, and hot plate tests were performed to evaluate cognitive, motor, and sensory functions, respectively. Following sacrification oxidative stress markers, cholinergic function, and proinflammatory cytokines were studied from brain homogenates. Cis impaired cognitive function and motor performance in the Cis and Cis+Vehicle groups. The drug also increased oxidative stress in the brain. Mel significantly improved brain oxidant/antioxidant status and also decreased the overproduction of proinflammatory cytokines (superoxide dismutase activities in Cis+Vehicle and Cis+Mel groups: 104.55 ± 9.50 µU/mg protein vs. 150.13 ± 4.70 µU/mg protein, respectively, p < 0.05; tumor necrosis factor-α levels in Cis and Cis+Mel groups: 40 pg/ml vs. 20 pg/ml, respectively, p < 0.05). It seems that Mel can improve Cis neurotoxicity. For a more firm conclusion, further studies using Mel at different doses with larger groups should be performed.

Hibiscus (Hibiscus sabdariffa L.) supplementation increases butyrate synthesis and reduces inflammatory cells, attenuating the formation of aberrant crypt foci in BALB/c mice induced to pre-neoplastic lesions

The development of colorectal cancer involves some morphological changes, and in the initial stage, pre-neoplastic lesions called aberrant crypt foci (ACF) appear. Thus, an intervention with sources of bioactive compounds such as Hibiscus sabdariffa L., rich in phenolic compounds and anthocyanins, could attenuate the risk of developing these lesions due to its antioxidant, anti-inflammatory and anti-proliferative properties. Therefore, the aim of this study was to evaluate the effects of 5% and 10% supplementation of dehydrated H. sabdariffa calyces (DHSC) during the development of 1,2-dimethylhydrazine-induced preneoplastic lesions in male BALB/c mice. The characterization of DHSC was carried out. The in vivo experiment lasted 12 weeks, and the animals were randomly divided into 3 experimental groups: the control group (CON) and the supplemented groups with 5% DHSC and 10% DHSC. The activities of liver enzymes catalase and superoxide dismutase were determined. In addition, ACF, short chain fatty acids (SCFA), presence of inflammatory infiltrates, goblet cells and leukocytes in the colonic mucosa were quantified. There was a significant reduction in ACF and the presence of inflammatory infiltrates in the colon of animals in groups 5DHSC and 10DHSC. In addition, the 10DHSC group showed an increase in the activity of the catalse enzyme, in the production of butyrate and in the presence of NK cells in the colon, in addition to more hypertrophied goblet cells. Based on these findings, it is suggested that DHSC supplementation may be recommended to attenuate cellular responses in the early stage of preneoplastic lesions.

Fish Collagen Peptides Protect against Cisplatin-Induced Cytotoxicity and Oxidative Injury by Inhibiting MAPK Signaling Pathways in Mouse Thymic Epithelial Cells

Thymic epithelial cells (TECs) account for the most abundant and dominant stromal component of the thymus, where T cells mature. Oxidative- or cytotoxic-stress associated injury in TECs, a significant and common problem in many clinical settings, may cause a compromised thymopoietic capacity of TECs, resulting in clinically significant immune deficiency disorders or impairment in the adaptive immune response in the body. The present study demonstrated that fish collagen peptides (FCP) increase cell viability, reduce intracellular levels of reactive oxygen species (ROS), and impede apoptosis by repressing the expression of Bax and Bad and the release of cytochrome c, and by upregulating the expression of Bcl-2 and Bcl-xL in cisplatin-treated TECs. These inhibitory effects of FCP on TEC damage occur via the suppression of ROS generation and MAPK (p38 MAPK, JNK, and ERK) activity. Taken together, our data suggest that FCP can be used as a promising protective agent against cytotoxic insults- or ROS-mediated TEC injury. Furthermore, our findings provide new insights into a therapeutic approach for the future application of FCP in the prevention and treatment of various types of oxidative- or cytotoxic stress-related cell injury in TECs as well as age-related or acute thymus involution.

Myricetin (3,3',4',5,5',7-hexahydroxyflavone) prevents ethanol-induced biochemical and inflammatory damage in the liver of Wistar rats

Purpose: The current investigation was carried out to evaluate the efficacy of myricetin in ethanol-induced liver toxicity in Wistar rats. Research Design: Twenty-four rats were randomly divided into four groups with six animals per group. Group-I animals were administered with vehicle (distilled water), Group II, III, and IV were treated orally with sequential (per week) increase in the dose of ethanol (5, 8, 10, and 12 g/kg b wt per week in each group) for 28 days. Myricetin was treated orally to Group-III and IV animals at the respective doses of 25 mg/kg b wt. and 50 mg/kg b wt. Results: Our results showed that myricetin prevented hepatotoxicity by modulating the production of free radicals, ethanol metabolizing enzymes, and inflammatory markers in vivo. Myricetin also helped maintain lipid membrane integrity, oxidant-antioxidant status, and histoarchitecture. Ethanol administration caused elevation in XO, ADH, and CYP2E1 in hepatic tissue, which significantly normalized with myricetin administration. After ethanol administration, there was a steep increase in the hepatotoxicity biomarkers, including ALT, MDA, and AST. The level of cytotoxicity marker LDH also increased after ethanol administration; myricetin administration decreased the level of all these markers. Moreover, myricetin treatment also reduced ethanol-induced inflammatory markers such as NF-κB and IL-6. Conclusion: Findings from the current study demonstrate that myricetin administration prevents alcohol-induced hepatic injury by influencing the metabolism of ethanol, inhibiting oxidative stress, maintaining lipid profile, and suppressing inflammatory markers.

Myricetin (3,3',4',5,5',7-Hexahydroxyflavone) Prevents 5-Fluorouracil-Induced Cardiotoxicity

5-Fluorouracil (5-FU) is a strong anti-cancer drug used to manage numerous cancers. Cardiotoxicity, renal toxicity, and liver toxicity are some of the adverse effects which confine its clinical use to some extent. 5-FU-induced organ injuries are associated with redox imbalance, inflammation, and damage to heart functioning, particularly in the present study. Myricetin is an abundant flavonoid, commonly extracted from berries and herbs having anti-oxidative and anti-cancer activities. We planned the current work to explore the beneficial effects of myricetin against 5-FU-induced cardiac injury in Wistar rats through a biochemical and histological approach. Prophylactic myricetin treatment at two doses (25 and 50 mg/kg) was given to rats orally for 21 days against cardiac injury induced by a single injection of 5-FU (150 mg/kg b.wt.) given on the 20th day intraperitoneally. The 5-FU injection induced oxidative stress, inflammation, and extensive cardiac damage. Nevertheless, myricetin alleviated markers of inflammation, apoptosis, cardiac toxicity, oxidative stress, and upregulated anti-oxidative machinery. The histology of heart further supports our biochemical findings mitigated by the prophylactic treatment of myricetin. Henceforth, myricetin mitigates 5-FU-induced cardiac damage by modulating oxidative stress, inflammation, and cardiac-specific markers, as found in the present study.

The Potential Role of Polyphenols in Oxidative Stress and Inflammation Induced by Gut Microbiota in Alzheimer's Disease

Gut microbiota (GM) play a role in the metabolic health, gut eubiosis, nutrition, and physiology of humans. They are also involved in the regulation of inflammation, oxidative stress, immune responses, central and peripheral neurotransmission. Aging and unhealthy dietary patterns, along with oxidative and inflammatory responses due to gut dysbiosis, can lead to the pathogenesis of neurodegenerative diseases, especially Alzheimer's disease (AD). Although the exact mechanism between AD and GM dysbiosis is still unknown, recent studies claim that secretions from the gut can enhance hallmarks of AD by disturbing the intestinal permeability and blood-brain barrier via the microbiota-gut-brain axis. Dietary polyphenols are the secondary metabolites of plants that possess anti-oxidative and anti-inflammatory properties and can ameliorate gut dysbiosis by enhancing the abundance of beneficial bacteria. Thus, modulation of gut by polyphenols can prevent and treat AD and other neurodegenerative diseases. This review summarizes the role of oxidative stress, inflammation, and GM in AD. Further, it provides an overview on the ability of polyphenols to modulate gut dysbiosis, oxidative stress, and inflammation against AD.

Natural-Derived Molecules as a Potential Adjuvant in Chemotherapy: Normal Cell Protectors and Cancer Cell Sensitizers

BACKGROUND

Cancer is a global threat to humans and a leading cause of death worldwide. Cancer treatment includes, among other things, the use of chemotherapeutic agents, compounds that are vital for treating and preventing cancer. However, chemotherapeutic agents produce oxidative stress along with other side effects that would affect the human body.

OBJECTIVE

To reduce the oxidative stress of chemotherapeutic agents in cancer and normal cells by naturally derived compounds with anti-cancer properties, and protect normal cells from the oxidation process. Therefore, the need to develop more potent chemotherapeutics with fewer side effects has become increasingly important.

METHOD

Recent literature dealing with the antioxidant and anticancer activities of the naturally naturally-derived compounds: morin, myricetin, malvidin, naringin, eriodictyol, isovitexin, daidzein, naringenin, chrysin, and fisetin has been surveyed and examined in this review. For this, data were gathered from different search engines, including Google Scholar, ScienceDirect, PubMed, Scopus, Web of Science, Scopus, and Scifinder, among others. Additionally, several patient offices such as WIPO, CIPO, and USPTO were consulted to obtain published articles related to these compounds.

RESULT

Numerous plants contain flavonoids and polyphenolic compounds such as morin, myricetin, malvidin, naringin, eriodictyol, isovitexin, daidzein, naringenin, chrysin, and fisetin, which exhibit ‎antioxidant, anti-inflammatory, and anti-carcinogenic actions via several mechanisms. These compounds show sensitizers of cancer cells and protectors of healthy cells. Moreover, these compounds can reduce oxidative stress, which is accelerated by chemotherapeutics and exhibit a potent anticancer effect on cancer cells.

CONCLUSIONS

Based on these findings, more research is recommended to explore and evaluate such flavonoids and polyphenolic compounds.

The Antioxidant Carrichtera annua DC. Ethanolic Extract Counteracts Cisplatin Triggered Hepatic and Renal Toxicities

Cisplatin is a powerful anti-neoplastic drug that displays multi-organ toxicity, especially to the liver and kidneys. Consumption of phytomedicines is a promising strategy to overcome the side effects of chemotherapy. Carrichtera annua extract proved to possess potent antioxidant activity. Its protective potential against cisplatin-induced hepato-nephrotoxicity was scrutinized. Moreover, a phytochemical study was conducted on C. annua ethyl acetate fraction which led to the isolation of five known phenolic compounds. Structure determination was achieved utilizing 1H- and 13C-NMR spectral analyses. The isolated phytochemicals were trans-ferulic acid (1), kaempferol (2), p-coumaric acid (3), luteolin (4) and quercetin (5). Regarding our biological study, C. annua has improved liver and kidney deteriorated functions caused by cisplatin administration and attenuated the histopathological injury in their tissues. Serum levels of ALT, AST, blood urea nitrogen and creatinine were significantly decreased. C. annua has modulated the oxidative stress mediated by cisplatin as it lowered MDA levels while enhanced reduced-GSH concentrations. More importantly, the plant has alleviated cisplatin triggered inflammation, apoptosis via reduction of INFγ, IL-1β and caspase-3 production. Moreover, mitochondrial injury has been ameliorated as remarkable increase of mtDNA was noted. Furthermore, the MTT assay proved the combination of cisplatin-C. annua extract led to growth inhibition of MCF-7 cells in a notable additive way. Additionally, we have investigated the binding affinity of C. annua constituents with caspase-3 and IFN-γ proteins using molecular simulation. All the isolated compounds exhibited good binding affinities toward the target proteins where quercetin possessed the most auspicious caspase-3 and IFN-γ inhibition activities. Our results put forward that C. annua is a promising candidate to counteract chemotherapy side effects and the observed activity could be attributed to the synergism between its phytochemicals.

Gut microbiota accelerates cisplatin-induced acute liver injury associated with robust inflammation and oxidative stress in mice

Background

Gut microbiota has been reported to be disrupted by cisplatin, as well as to modulate chemotherapy toxicity. However, the precise role of intestinal microbiota in the pathogenesis of cisplatin hepatotoxicity remains unknown.

Methods

We compared the composition and function of gut microbiota between mice treated with and without cisplatin using 16S rRNA gene sequencing and via metabolomic analysis. For understanding the causative relationship between gut dysbiosis and cisplatin hepatotoxicity, antibiotics were administered to deplete gut microbiota and faecal microbiota transplantation (FMT) was performed before cisplatin treatment.

Results

16S rRNA gene sequencing and metabolomic analysis showed that cisplatin administration caused gut microbiota dysbiosis in mice. Gut microbiota ablation by antibiotic exposure protected against the hepatotoxicity induced by cisplatin. Interestingly, mice treated with antibiotics dampened the mitogen-activated protein kinase pathway activation and promoted nuclear factor erythroid 2-related factor 2 nuclear translocation, resulting in decreased levels of both inflammation and oxidative stress in the liver. FMT also confirmed the role of microbiota in individual susceptibility to cisplatin-induced hepatotoxicity.

Conclusions

This study elucidated the mechanism by which gut microbiota mediates cisplatin hepatotoxicity through enhanced inflammatory response and oxidative stress. This knowledge may help develop novel therapeutic approaches that involve targeting the composition and metabolites of microbiota.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-02814-5.

Taxifolin ameliorates Benzo[a]pyrene-induced lung injury possibly via stimulating the Nrf2 signalling pathway

Benzo[a]pyrene, an environmental contaminant as well as a mutagen is widely found in cigarette smoke, automobile exhaust particles among other sources. The present study underlines the protective effect of Taxifolin on B[a]P induced lung injury in male Swiss Albino Mice by analyzing the activity/level of various pro and anti-oxidant parameters, Inflammatory markers, Phase II enzyme, as well as lung histology. Taxifolin was administered orally to mice at either dose of 20 or 40 mg/kg body weight for 14 days and then challenged with a single dose of B[a]P (125 mg/kg body weight by oral gavage) on the 14th day. Our results show treatment with B[a]P leads to increased activity/level of CYP450R, EH, pro-inflammatory proteins, as well as lipid peroxidation and reduce level/activity of anti-oxidant molecules while Taxifolin treatment shows ameliorative effect. Administration of B[a]P also leads to decrease in expression of ROS sensitive factor Nrf2 and its downstream target NQO1,HO-1,SOD while Taxifolin treated animals showed a very high level of expression of Nrf2,NQO1,HO-1,SOD. Since Nrf2 plays central role in providing resistance to oxidative stress and also suppresses inflammation by inhibiting NF-κB,we concluded Taxifolin suppresses oxidative stress and inflammation in B[a]P induced lung injury possibly via stimulating the Nrf2 signaling pathway.

Amelioration of N,N'-dimethylhydrazine induced colon toxicity by epigallocatechin gallate in Wistar rats

Colon cancer is a life-threatening disease all over the world and is linked to constant oxidative stress and inflammation. Epigallocatechin gallate (EGCG), is a naturally occurring flavone possessing health benefiting pharmacological properties including antioxidant, anti-inflammatory and free radical scavenging properties. Our study investigates the role of EGCG on N,N'-dimethylhydrazine (DMH), a toxic environmental pollutant, induced colon toxicity. To investigate the effect of EGCG, Wistar rats were given EGCG for 7 days at the two doses of 10 and 20 mg/kg body weight and DMH was injected on the seventh day in all the group rats except the control. Our results indicate that DMH administration increased the oxidative stress (MDA) and depleted the glutathione and antioxidant enzyme activities (SOD, CAT, GR, GST and GPx) which was significantly ameliorated by EGCG treatment. Additionally DMH treatment upregulated inflammatory markers expression (NF-κB, COX-2 and IL-6) and enhanced mucosal damage in the colon. EGCG treatment significantly reduced inflammation and restored the normal histoarchitecture of the colon. We can conclude from the present study findings that EGCG protects the colon from DMH toxicity through its antioxidant and anti-inflammatory potential.

Quercetin ameliorates reactive oxygen species generation, inflammation, mucus depletion, goblet disintegration, and tumor multiplicity in colon cancer: Probable role of adenomatous polyposis coli, β-catenin

1,2 Dimethyl hydrazine (DMH), a cogent environmental toxicant, targets the colon. Previous reports suggest that DMH-mediated dysregulation of the Wnt/β-catenin pathway plays a vital role in the initial events of colon carcinogenesis. Our study was designed to investigate the effect of quercetin on DMH-mediated colon cancer by targeting adenomatous polyposis coli (APC) and β-catenin in Wistar rats. Animals were pretreated orally with quercetin at doses of either 25 or 50 mg/kg bodyweight (bw) and DMH at a dose of 20 mg/kg bw subcutaneously up to the 15th week and sacrificed after the 30th week. DMH administration leads to reactive oxygen species generation, resulting in an imbalance in redox homeostasis and causing membrane lipid peroxidation, which is also partly due to the decrease in the level of tissue antioxidant machinery. Increased inflammatory and proliferative proteins were observed in DMH-induced colon cancerous rats. DMH treatment also led to dysregulation in the apoptotic pathway with decreased Bax:Bcl-2 ratio. Quercetin pretreatment ameliorates DMH-induced proliferation, activities of detoxifying enzymes, and putative early markers (mucin depletion and goblet cell disintegration) in colonic tissue. It also significantly regulates APC and β-catenin expression and inhibits tumor incidence and multiplicity. Histological results further confirm the beneficial role of quercetin in averting DMH-induced pathological alterations.

Myricetin: A review of the most recent research

Myricetin(MYR) is a flavonoid compound widely found in many natural plants including bayberry. So far, MYR has been proven to have multiple biological functions and it is a natural compound with promising research and development prospects. This review comprehensively retrieved and collected the latest pharmacological abstracts on MYR, and discussed the potential molecular mechanisms of its effects. The results of our review indicated that MYR has a therapeutic effect on many diseases, including tumors of different types, inflammatory diseases, atherosclerosis, thrombosis, cerebral ischemia, diabetes, Alzheimer's disease and pathogenic microbial infections. Furthermore, it regulates the expression of Hippo, MAPK, GSK-3β, PI3K/AKT/mTOR, STAT3, TLR, IκB/NF-κB, Nrf2/HO-1, ACE, eNOS / NO, AChE and BrdU/NeuN. MYR also enhances the immunomodulatory functions, suppresses cytokine storms, improves cardiac dysfunction, possesses an antiviral potential, can be used as an adjuvant treatment against cancer, cardiovascular injury and nervous system diseases, and it may be a potential drug against COVID-19 and other viral infections. Generally, this article provides a theoretical basis for the clinical application of MYR and a reference for its further use.

Topical Wound Healing Activity of Myricetin Isolated from Tecomaria capensis v. aurea

Wounds and burn injury are major causes of death and disability worldwide. Myricetin is a common bioactive flavonoid isolated naturally from the plant kingdom. Herein, a topical application of naturally isolated myricetin from the shoots of Tecomaria capensis v. aurea on excisional wound healing that was performed in albino rats. The wounded rats were treated every day with 10 and 20% myricetin for 14 days. During the experiment, the wound closure percentage was estimated at days 0, 7, and 14. Effects of myricetin on the inflammatory cytokines (tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and cluster of differentiation 68 (CD68) in the serum were evaluated using immunosorbent assay kits. The percentage of wound closure and contraction was delayed in wounded rats (67.35%) and was remarkably increased after treatment of wounded rats with myricetin; the treatment with 20% myricetin was the most potent (98.76%). Histological findings exhibited that 10% myricetin caused the formation of a large area of scarring at the wound enclosure and stratified squamous epithelium without the formation of papillae as in the control group. Treatment with 20% myricetin exhibited less area of scarring at the wound enclosure as well as re-epithelialization with a high density of fibroblasts and blood capillaries in the wound. Level elevations of serum pro-inflammatory cytokines, IL-1β, and TNF-α and macrophage CD68 were decreased in wounded rats treated with myricetin. Thus, it can be suggested that the enhancements in inflammatory cytokines as well as systemic reorganization after myricetin treatment may be recommended to play a crucial part in the promotion of wound healing. The findings suggest that treatment with a higher dose of myricetin was better in improving wound curing in rats. It could serve as a potent anti-inflammatory agent and can be used as an adjunctive or alternative agent in the future.

The anti-STAT1 polyphenol myricetin inhibits M1 microglia activation and counteracts neuronal death

Microglia activation toward M1 pro-inflammatory phenotype represents one of the earliest events of neurological disorders. Therefore, reducing microglia activation should inhibit neuroinflammation, thereby delaying the progression of neurodegeneration. Recently, we pointed out the role of STAT1 signaling in hypoxia-induced M1 activation and proposed STAT1 as a suitable molecular target for the prevention and treatment of neurodegeneration. Myricetin (MYR) is a natural flavonoid that exhibits a specific anti-STAT1 activity correlated with its direct interaction with STAT1 protein itself. Herein, we investigated the anti-inflammatory effect of MYR and its ability to protect neurons from death in an in vitro model of neurotoxicity using the neuroblast-like SH-SY5Y cells that were exposed to conditioned media from hypoxia-activated microglia BV2 cells. We demonstrate that MYR pretreatment is able to switch off hypoxia-induced M1 microglia polarization through the inhibition of STAT1 signaling. The analysis of the molecular mechanism suggests that the direct interaction of MYR with STAT1 impairs its S-glutathionylation and phosphorylation. Moreover, treatment of SH-SY5Y cells with conditioned medium from hypoxia-activated microglia pretreated with MYR produced a significant reduction in neuronal viability. Our data indicate that MYR may represent a promising candidate for prevention and treatment of neuroinflammation in neurodegenerative disorders.

Ethyl acetate extract from Cistus x incanus L. leaves enriched in myricetin and quercetin derivatives, inhibits inflammatory mediators and activates Nrf2/HO-1 pathway in LPS-stimulated RAW 264.7 macrophages

Cistus x incanus L. is a Mediterranean evergreen shrub used in folk medicine for the treatment of inflammatory disorders but the underlying mechanisms are not fully understood. We therefore investigated the anti-inflammatory effects of an ethyl acetate fraction (EAF) from C. x incanus L. leaves on lipopolysaccharide (LPS) activated RAW 264.7 macrophages. HPLC analysis revealed myricetin and quercetin derivatives to be the major compounds in EAF; EAF up to 1 µM of total phenolic content, was not cytotoxic and inhibited the mRNA expression of interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2) (p < 0.05) and the production of prostaglandins E₂ (PGE₂) (p < 0.05). Meanwhile, EAF triggered the mRNA expression of interleukin-10 (IL-10) and elicited the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2), as well as the expression of its main target gene, heme oxygenase-1 (HO-1) (p < 0.05). These data indicate that EAF attenuates experimental inflammation via the inhibition of proinflammatory mediators and at least in part, by the activation of Nrf2/HO-1 pathway. These effects are likely due to myricetin and quercetin derivatives but the role of other, less abundant components cannot be excluded. Further studies to confirm the relevance of our findings in animal models and to highlight the relative contribution of each component to the anti-inflammatory activity of EAF should be conducted.

Current Pharmacological Trends on Myricetin

Myricetin is a member of the group of flavonoids called flavonols. Myricetin is obtained from various fruit, vegetables, tea, berries and red wine. Myricetin is characterized by the pysrogallol B-ring, and the more hydroxylated structure is known to be capable for its increased biological properties compared with other flavonols. Myricetin is produced by the Myricaceae, Anacardiaceae, Polygonaceae, Pinaceae and Primulacea families. It is soluble in organic solvent such as ethanol, DMSO (dimethyl sulfoxide), and dimethyl formamide (DMF). It is sparingly soluble in aqueous buffers. Myricetin shows its various pharmacological activities including antioxidant, anti-amyloidogenic, antibacterial, antiviral, antidiabetic, anticancer, anti-inflammatory, anti-epileptic and anti-ulcer. This review article focuses on pharmacological effects of Myricetin on different diseases such as osteoporotic disorder, anti-inflammatory disorder, alzheimer’s disease, anti-epileptic, cancer, cardiac disorder, diabetic metabolic disorder, hepatoprotective disorder and gastro protective disorder.

Protective Effects of Myricetin on Benzo[a]pyrene-Induced 8-Hydroxy-2'-Deoxyguanosine and BPDE-DNA Adduct

Benzo[a]pyrene (B[a]P), a group 1 carcinogen, induces mutagenic DNA adducts. Myricetin is present in many natural foods with diverse biological activities, such as anti-oxidative and anti-cancer activities. The aim of this study was to investigate the protective effects of myricetin against B[a]P-induced toxicity. Treatment of B[a]P induced cytotoxicity on HepG2 cells, whereas co-treatment of myricetin with B[a]P reduced the formation of the B[a]P-7,8-dihydrodiol-9,10-epoxide (BPDE)-DNA adduct, which recovered cell viability. Furthermore, we found a protective effect of myricetin against B[a]P-induced genotoxicity in rats, via myricetin-induced inhibition of 8-hydroxy-2′-deoxyguanosine (8-OHdG) and BPDE-DNA adduct formation in the liver, kidney, colon, and stomach tissue. This inhibition was more prominent in the liver than in other tissues. Correspondingly, myricetin regulated the phase I and II enzymes that inhibit B[a]P metabolism and B[a]P metabolites conjugated with DNA by reducing and inducing CYP1A1 and glutathione S-transferase (GST) expression, respectively. Taken together, this showed that myricetin attenuated B[a]P-induced genotoxicity via regulation of phase I and II enzymes. Our results suggest that myricetin is anti-genotoxic, and prevents oxidative DNA damage and BPDE-DNA adduct formation via regulation of phase I and II enzymes.