Resveratrol alleviates oxidative stress caused by Streptococcus uberis infection via activating the Nrf2 signaling pathway

Polyphenols and Lactation: Molecular Evidence to Support the Use of Botanical Galactagogues

Botanicals and herbal supplements contain a diverse array of polyphenols that may affect mammary gland function and promote galactagogue activity. This scoping review is conducted to identify scientific literature elucidating how polyphenols affect mammary gland biology and cellular mechanisms critical for lactation. A literature search of PubMed and Medline reviews relevant studies in dairy animals, rodent models, and cultured mammary epithelial cells that are published from January 2010 until July 2023, to ascertain effects of polyphenols on mechanisms regulating milk production and composition. The PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Review) strategy is applied and 80 studies on polyphenols and their implications on milk production and composition are included in this review. Limited information delineating effects of polyphenols on the molecular pathways that affect lactation are found, although available information suggests modulation of Stat5 signaling/differentiation, Stat3 signaling/remodeling, mTOR and insulin signaling/energy production, and nuclear factor kappa beta (NFκβ) signaling/oxidative stress and inflammation may play roles. A profound lack of mechanistic information underscores the critical need for further research to understand the impact of botanical supplements and polyphenols on milk production and composition in humans to establish maternal nutritional guidelines to support lactation and breastfeeding goals.

E-Stilbenes: General Chemical and Biological Aspects, Potential Pharmacological Activity Based on the Nrf2 Pathway

Stilbenes are phytoalexins, and their biosynthesis can occur through a natural route (shikimate precursor) or an alternative route (in microorganism cultures). The latter is a metabolic engineering strategy to enhance production due to stilbenes recognized pharmacological and medicinal potential. It is believed that in the human body, these potential activities can be modulated by the regulation of the nuclear factor erythroid derived 2 (Nrf2), which increases the expression of antioxidant enzymes. Given this, our review aims to critically analyze evidence regarding E-stilbenes in human metabolism and the Nrf2 activation pathway, with an emphasis on inflammatory and oxidative stress aspects related to the pathophysiology of chronic and metabolic diseases. In this comprehensive literature review, it can be observed that despite the broad number of stilbenes, those most frequently explored in clinical trials and preclinical studies (in vitro and in vivo) were resveratrol, piceatannol, pterostilbene, polydatin, stilbestrol, and pinosylvin. In some cases, depending on the dose/concentration and chemical nature of the stilbene, it was possible to identify activation of the Nrf2 pathway. Furthermore, the use of some experimental models presented a challenge in comparing results. In view of the above, it can be suggested that E-stilbenes have a relationship with the Nrf2 pathway, whether directly or indirectly, through different biological pathways, and in different diseases or conditions that are mainly related to inflammation and oxidative stress.

Antioxidative Sirt1 and the Keap1-Nrf2 Signaling Pathway Impair Inflammation and Positively Regulate Autophagy in Murine Mammary Epithelial Cells or Mammary Glands Infected with Streptococcus uberis

Streptococcus uberis mastitis in cattle infects mammary epithelial cells. Although oxidative responses often remove intracellular microbes, S. uberis survives, but the mechanisms are not well understood. Herein, we aimed to elucidate antioxidative mechanisms during pathogenesis of S. uberis after isolation from clinical bovine mastitis milk samples. S. uberis's in vitro pathomorphology, oxidative stress biological activities, transcription of antioxidative factors, inflammatory response cytokines, autophagosome and autophagy functions were evaluated, and in vivo S. uberis was injected into the fourth mammary gland nipple of each mouse to assess the infectiousness of S. uberis potential molecular mechanisms. The results showed that infection with S. uberis induced early oxidative stress and increased reactive oxygen species (ROS). However, over time, ROS concentrations decreased due to increased antioxidative activity, including total superoxide dismutase (T-SOD) and malondialdehyde (MDA) enzymes, plus transcription of antioxidative factors (Sirt1, Keap1, Nrf2, HO-1). Treatment with a ROS scavenger (N-acetyl cysteine, NAC) before infection with S. uberis reduced antioxidative responses and the inflammatory response, including the cytokines IL-6 and TNF-α, and the formation of the Atg5-LC3II/LC3I autophagosome. Synthesis of antioxidants determined autophagy functions, with Sirt1/Nrf2 activating autophagy in the presence of S. uberis. This study demonstrated the evasive mechanisms of S. uberis in mastitis, including suppressing inflammatory and ROS defenses by stimulating antioxidative pathways.

The Use of Fruit and Vegetable by-Products as Enhancers of Health Status of Piglets after Weaning: The Role of Bioactive Compounds from Apple and Carrot Industrial Wastes

At weaning, piglets are exposed to a large variety of stressors, from environmental/behavioral factors to nutritional stress. Weaning transition affects the gastrointestinal tract especially, resulting in specific disturbances at the level of intestinal morphology, barrier function and integrity, mucosal immunity and gut microbiota. All these alterations are associated with intestinal inflammation, oxidative stress and perturbation of intracellular signaling pathways. The nutritional management of the weaning period aims to achieve the reinforcement of intestinal integrity and functioning to positively modulate the intestinal immunity and that of the gut microbiota and to enhance the health status of piglets. That is why the current research is focused on the raw materials rich in phytochemicals which could positively modulate animal health. The composition analysis of fruit, vegetable and their by-products showed that identified phytochemicals could act as bioactive compounds, which can be used as modulators of weaning-induced disturbances in piglets. This review describes nutritional studies which investigated the effects of bioactive compounds derived from fruit (apple) and vegetables (carrot) or their by-products on the intestinal architecture and function, inflammatory processes and oxidative stress at the intestinal level. Data on the associated signaling pathways and on the microbiota modulation by bioactive compounds from these by-products are also presented.

A comprehensive insight into the molecular and cellular mechanisms of action of resveratrol on complications of sepsis a systematic review

Sepsis and septic shock are still one of the most important medical challenges. Sepsis is an extreme and uncontrolled response of the innate immune system to invading pathogenesis. Resveratrol (3,5,4'-trihydroxytrans-stilbene), is a phenolic and non-flavonoid compound naturally produced by some plants and fruits. The object of the current study is to systematically review the impacts of resveratrol and its mechanisms of function in the management of sepsis and its related complications. The guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statements were applied to perform the study (PROSPERO: CRD42021289357). We searched Embase, Web of Science, Google Scholar, Science Direct, PubMed, ProQuest, and Scopus databases up to January 2023 by using the relevant keywords. Study criteria were met by 72 out of 1415 articles screened. The results of this systematic review depict that resveratrol can reduces the complications of sepsis by affecting inflammatory pathways, oxidative stress, and modulating immune responses. Future human randomized clinical trials are necessary due to the promising therapeutic effects of resveratrol on sepsis complications and the lack of clinical trials in this regard.

The protective effect of resveratrol on largemouth bass (Micropterus salmoides) during out-of-season spawning

In aquaculture production, out-of-season spawning is beneficial to solve the seasonal shortage of fry that are normally produced once annually by species such as largemouth bass (Micropterus salmoides), thereby implementing year-round fry production. Maintaining low temperature over a period of several months can delay largemouth bass ovarian development, but it can cause severe stress to their reproductive function, leading to decreased fertility during out-of-season spawning. Feeding with antioxidants is one of the most effective methods to alleviate the negative effects of low temperature stress. Therefore, the purpose of this study is to: (a) evaluate the changes in oocyte morphology, antioxidant capacity, reproductive hormone-related index, cell apoptosis and autophagy during the out-of-season spawning of largemouth bass, and (b) to investigate the protective effect of the antioxidant resveratrol on this fish during out-of-season spawning from May through August. The study was divided into two groups (three replicates per group, 2000 fish per replicate): control group (Control) (exposure to water temperature of 12-17 °C) and resveratrol supplementation group (Res) (exposure to water temperature of 12-17 °C and fed with 200 mg/kg resveratrol). The results show that: (1) The serum hormones LH and E2 increased first and then remained unchanged, and the ovarian section showed that the ovary remained in stage IV. (2) In the process of off-season reproduction, a large number of follicles experienced follicular atresia, accompanied by endoplasmic reticulum expansion, nuclear chromatin condensation and mitochondrial swelling, which was relieved after feeding resveratrol. (3) Resveratrol decreased the ovarian ROS content and improved the activities of CAT and other antioxidant enzymes in the ovary and liver to some extent. (4) Resveratrol reduced the level of pro-apoptotic (Bax, Caspase3, Caspase8, Caspase9) and autophagy-related components (LC3-B, Beclin-1) while increasing the transcription level of anti-apoptotic (Bcl-2) factors. These findings suggest that resveratrol alleviates some adverse effects of largemouth bass during out-of-season spawning to some extent and provide a model for efficient and high-quality out-of-season spawning.

The Complex Genetic and Epigenetic Regulation of the Nrf2 Pathways: A Review

Nrf2 is a major transcription factor that significantly regulates-directly or indirectly-more than 2000 genes. While many of these genes are involved in maintaining redox balance, others are involved in maintaining balance among metabolic pathways that are seemingly unrelated to oxidative stress. In the past 25 years, the number of factors involved in the activation, nuclear translocation, and deactivation of Nrf2 has continued to expand. The purpose of this review is to provide an overview of the remarkable complexity of the tortuous sequence of stop-and-go signals that not only regulate expression or repression, but may also modify transcriptional intensity as well as the specificity of promoter recognition, allowing fluidity of its gene expression profile depending on the various structural modifications the transcription factor encounters on its journey to the DNA. At present, more than 45 control points have been identified, many of which represent sites of action of the so-called Nrf2 activators. The complexity of the pathway and the synergistic interplay among combinations of control points help to explain the potential advantages seen with phytochemical compositions that simultaneously target multiple control points, compared to the traditional pharmaceutical paradigm of "one-drug, one-target".

Resveratrol in breast cancer treatment: from cellular effects to molecular mechanisms of action

Breast cancer (BC) is one of the most common cancers in females and is responsible for the highest cancer-related deaths following lung cancer. The complex tumor microenvironment and the aggressive behavior, heterogenous nature, high proliferation rate, and ability to resist treatment are the most well-known features of BC. Accordingly, it is critical to find an effective therapeutic agent to overcome these deleterious features of BC. Resveratrol (RES) is a polyphenol and can be found in common foods, such as pistachios, peanuts, bilberries, blueberries, and grapes. It has been used as a therapeutic agent for various diseases, such as diabetes, cardiovascular diseases, inflammation, and cancer. The anticancer mechanisms of RES in regard to breast cancer include the inhibition of cell proliferation, and reduction of cell viability, invasion, and metastasis. In addition, the synergistic effects of RES in combination with other chemotherapeutic agents, such as docetaxel, paclitaxel, cisplatin, and/or doxorubicin may contribute to enhancing the anticancer properties of RES on BC cells. Although, it demonstrates promising therapeutic features, the low water solubility of RES limits its use, suggesting the use of delivery systems to improve its bioavailability. Several types of nano drug delivery systems have therefore been introduced as good candidates for RES delivery. Due to RES's promising potential as a chemopreventive and chemotherapeutic agent for BC, this review aims to explore the anticancer mechanisms of RES using the most up to date research and addresses the effects of using nanomaterials as delivery systems to improve the anticancer properties of RES.

The Role of Resveratrol in Mild Cognitive Impairment and Alzheimer's Disease: A Systematic Review

Advancing age is one of the risk factors for developing many diseases, including cancer, cardiovascular disorders, and neurodegenerative alterations, such as mild cognitive impairment (MCI), and Alzheimer's Disease (AD). Studies have indicated that supplementation with resveratrol (RSV) might improve cerebrovascular function and reduce the risk of developing dementia. Thus, the aim of this systematic review was to assess the effects of RSV on MCI and AD. MEDLINE-PubMed, Cochrane, and EMBASE were used to perform the search, and PRISMA guidelines were followed. Five studies met the eligible criteria; three with AD and two with MCI. In AD patients, the use of RSV reduces Aβ levels, improves brain volume, reduces the Mini-mental status score, and improves AD scores. In patients with MCI, this polyphenol prevents decline in Standard Volumes of Interest and increases the Resting-state Functional Connectivity score. RSV can activate the human silent information regulator 2/sirtuin 1 (Sirt-1) and can inhibit the cyclooxygenase-2 (COX-2), 5-lipoxygenase, and nuclear factor-κB, resulting in the reduction of the proinflammation pathways. It is also associated with the increase in the levels of interleukin (IL)-10 and reduction of interferon-γ and IL-17. Both anti-inflammatory and antioxidant effects can be related to preventing neurodegenerative diseases, doing maintenance, and enabling the recovery of these conditions directly related to inflammation and oxidative stress. We suggest that the use of RSV can bring beneficial effects to patients with MCI or AD.

Activation of p62-NRF2 Axis Protects against Doxorubicin-Induced Ferroptosis in Cardiomyocytes: A Novel Role and Molecular Mechanism of Resveratrol

Doxorubicin (DOX) is a most common anthracycline chemotherapeutic agent; however, its clinical efficacy is limited due to its severe and irreversible cardiotoxicity. Ferroptosis, characterized by iron overload and lipid peroxidation, plays a pivotal role in DOX-induced cardiotoxicity. Resveratrol (RSV) displays cardioprotective and anticancer effects, owing to its antioxidative and anti-inflammatory properties. However, the role and mechanism of RSV in DOX-mediated ferroptosis in cardiomyocytes is unclear. This study showed that DOX decreased cell viability, increased iron accumulation and lipid peroxidation in H9c2 cells; however, these effects were reversed by RSV and ferroptosis inhibitor ferrostatin-1 (Fer-1) pre-treatment. Additionally, RSV significantly increased the cell viability of H9c2 cells treated with ferroptosis inducers Erastin (Era) and RSL3. Mechanistically, RSV inhibited mitochondrial reactive oxygen species (mtROS) overproduction and upregulated the p62-NRF2/HO-1 pathway. RSV-induced NRF2 activation was partially dependent on p62, and the selective inhibition of p62 (using p62-siRNA interference) or NRF2 (using NRF2 specific inhibitor, ML385) significantly abolished the anti-ferroptosis function of RSV. Furthermore, RSV treatment protected mice against DOX-induced cardiotoxicity, including significantly improving left ventricular function, ameliorating myocardial fibrosis and suppressing ferroptosis. Consistent with in vitro results, RSV also upregulated the p62-NRF2/HO-1 expression, which was inhibited by DOX, in the myocardium. Notably, the protective effect of RSV in DOX-mediated ferroptosis was similar to that of Fer-1 in vitro and in vivo. Thus, the p62-NRF2 axis plays a critical role in regulating DOX-induced ferroptosis in cardiomyocytes. RSV as a potent p62 activator has potential as a therapeutic target in preventing DOX-induced cardiotoxicity via ferroptosis modulation.

Immune response variations and intestinal flora changes in mastitis induced by three Streptococcus uberis strains

Streptococcus uberis is a common cause of mastitis. The pathogenicity among different strains of S. uberis and the resultant host immune responses remain to be elucidated. Herein, we document immune responses among three strains of S. uberis, and preliminary explore whether and how intestinal immunity plays a role in host anti-infection processes. Mice have been proved to be effective experimental animals for bovine mastitis, so utilizing a mouse intramammary infection model, we assay immune responses and gut flora changes of three S. uberis strains by histopathologic examination, RT-PCR, Western blot, and 16s ribosomal DNA sequencing. We find that the immune responses among the three sequence-type (ST) S. uberis strains may be linked to the hasA/B and lbp virulence genes, and the beta diversity of the intestine may be independent of the ST of S. uberis. Twenty phyla and 30 genera of intestinal flora were identified, with Verrucomicrobia and Akkermansia being the most prominent phylum and genus, respectively. These bacteria have strong anti-inflammatory and protective effects against S. uberis challenge. These data provide a foundation for further studies to elucidate gut flora function and exploration of therapeutic targets for mastitis.

Taurine protects blood-milk barrier integrity via limiting inflammatory response in Streptococcus uberis infections

Streptococcus uberis (S. uberis) is an important causative agent of mastitis, leading to significant economic losses to dairy industry. This research used a mouse mastitis model to investigate the protective effects of taurine on mammary inflammatory response and blood-milk barrier integrity in S. uberis challenge. The results showed that taurine attenuated S. uberis-induced mammary histopathological changes, especially neutrophil infiltration. The S. uberis-induced expression of pro-inflammatory mediators were decreased significantly by taurine. Further, we demonstrated that taurine limited the S. uberis-induced inflammatory responses via inhibiting the activation of NF-κB and MAPK signaling pathways. Inflammation usually disrupts the mammary barrier system. The recovery of claudin-3 and occludin expressions indicated that attenuation of inflammatory response by taurine can protect the integrity of blood-milk barrier in S. uberis infection. Taken together, our results reveal that the development of taurine as an effective prevention and control strategy for S. uberis-induced mastitis.

Recent Advances in Health Benefits of Stilbenoids

Biological targeting or molecular targeting is the main strategy in drug development and disease prevention. However, the problem of "off-targets" cannot be neglected. Naturally derived drugs are preferred over synthetic compounds in pharmaceutical markets, and the main goals are high effectiveness, lower cost, and fewer side effects. Single-target drug binding may be the major cause of failure, as the pathogenesis of diseases is predominantly multifactorial. Naturally derived drugs are advantageous because they are expected to have multitarget effects, but not off-targets, in disease prevention or therapeutic actions. The capability of phytochemicals to modulate molecular signals in numerous diseases has been widely discussed. Among them, stilbenoids, especially resveratrol, have been well-studied, along with their potential molecular targets, including AMPK, Sirt1, NF-κB, PKC, Nrf2, and PPARs. The analogues of resveratrol, pterostilbene, and hydroxylated-pterostilbene may have similar, if not more, potential biological targeting effects compared with their original counterpart. Furthermore, new targets that have been discussed in recent studies are reviewed in this paper.

Research Progress on Oxidative Stress and Its Nutritional Regulation Strategies in Pigs

Oxidative stress refers to the dramatic increase in the production of free radicals in human and animal bodies or the decrease in the ability to scavenging free radicals, thus breaking the antioxidation-oxidation balance. Various factors can induce oxidative stress in pig production. Oxidative stress has an important effect on pig performance and healthy growth, and has become one of the important factors restricting pig production. Based on the overview of the generation of oxidative stress, its effects on pigs, and signal transduction pathways, this paper discussed the nutritional measures to alleviate oxidative stress in pigs, in order to provide ideas for the nutritional research of anti-oxidative stress in pigs.