Compendium of naringenin: potential sources, analytical aspects, chemistry, nutraceutical potentials and pharmacological profile

Antimicrobial Activity of Grapefruit Seed Extract on Edible Mushrooms Contaminations: Efficacy in Preventing Pseudomonas spp. in Pleurotus eryngii

Pleurotus eryngii is an edible mushroom that suffers significant losses due to fungal contamination and bacteriosis. The Pseudomonadaceae family represents one of the most frequent etiologic agents. Grapefruit seed extract (GSE) is a plant extract that contains different bioactive components, such as naringin, and exhibits a strong antibacterial and antioxidant activity. Over the last decade, GSE use as an alternative to chemical treatments in the food sector has been tested. However, to our knowledge, its application on mushroom crops has never been investigated. This study focuses on evaluating GSE efficacy in preventing P. eryngii yellowing. GSE antibiotic activity, inhibitory and bactericidal concentrations, and antibiofilm activity against several microorganisms were tested with the Kirby-Bauer disk diffusion assay, the broth microdilution susceptibility test, and the Crystal violet assay, respectively. In vitro, the extract exhibited antimicrobial and antibiofilm activity against Staphylococcus aureus 6538 and MRSA (wild type), Escherichia coli ATCC 8739, and Pseudomonas spp. (Pseudomonas aeruginosa 9027, P. fluorescens (wild type)). GSE application in vivo, in pre- and post-sprouting stages, effectively prevented bacterial infections and subsequent degradation in the mushroom crops: none of the P. eryngii treated manifested bacteriosis. Our findings support the use of GSE as an eco-friendly and sustainable alternative to chemical treatments for protecting P. eryngii crops from bacterial contamination, consequently ensuring food safety and preventing financial losses due to spoilage. Furthermore, GSE's potential health benefits due to its content in naringin and other bioactive components present new possibilities for its use as a nutraceutical in food fortification and supplementation.

Potential of Plant-Derived Compounds in Preventing and Reversing Organ Fibrosis and the Underlying Mechanisms

Increased production of extracellular matrix is a necessary response to tissue damage and stress. In a normal healing process, the increase in extracellular matrix is transient. In some instances; however, the increase in extracellular matrix can persist as fibrosis, leading to deleterious alterations in organ structure, biomechanical properties, and function. Indeed, fibrosis is now appreciated to be an important cause of mortality and morbidity. Extensive research has illustrated that fibrosis can be slowed, arrested or even reversed; however, few drugs have been approved specifically for anti-fibrotic treatment. This is in part due to the complex pathways responsible for fibrogenesis and the undesirable side effects of drugs targeting these pathways. Natural products have been utilized for thousands of years as a major component of traditional medicine and currently account for almost one-third of drugs used clinically worldwide. A variety of plant-derived compounds have been demonstrated to have preventative or even reversal effects on fibrosis. This review will discuss the effects and the underlying mechanisms of some of the major plant-derived compounds that have been identified to impact fibrosis.

Paradigms and Success Stories of Natural Products in Drug Discovery Against Neurodegenerative Disorders (NDDs)

Neurodegenerative disorders (NDDs) are multifaceted complex disorders that have put a great health and economic burden around the globe nowadays. The multi-factorial nature of NDDs has presented a great challenge in drug discovery and continuous efforts are in progress in search of suitable therapeutic candidates. Nature has a great wealth of active principles in its lap that has cured the human population since ancient times. Natural products have revealed several benefits over conventional synthetic medications and scientists have shifted their vision towards exploring the therapeutic potentials of natural products in the past few years. The structural mimicking of natural compounds to endogenous ligands has presented them as a potential therapeutic candidate to prevent the development of NDDs. In the presented review, authors have summarized demographical facts about various NDDs including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD) and various types of sclerosis in the brain. The significant findings of new active principles of natural origin along with their therapeutic potentials on NDDs have been included. Also, a description of clinical trials and patents on natural products has been enlisted in this compilation. Although natural products have shown promising success in drug discovery against NDDs, still their use is associated with several ethical issues which need to be solved in the upcoming time.

A Compiled Update on Nutrition, Phytochemicals, Processing Effects, Analytical Testing and Health Effects of Chenopodium album: A Non-Conventional Edible Plant (NCEP)

Bathua (Chenopodium album) is a rich source of extensive-ranging nutrients, including bio-active carbohydrates, flavonoids and phenolics, minerals, and vitamins that translate to countless health benefits such as anticancer, antidiabetic, anti-inflammatory, antimicrobial, and antioxidant activity. Ascaridole, an important phytoconstituent present in aerial parts of the plant, contributes to its anthelmintic property. Even with vast historical use and significant health benefits, its renown has not spread, and utilization has significantly decreased in recent decades. Gradually, the plant has become known under the name of Non-conventional edible plant (NCEP). This compilation is prepared to bring out the plant under the spotlight for further research by foregrounding previous studies on the plant. Scientific research databases, including PubMed, Google Scholar, Scopus, SpringerLink, ScienceDirect, and Wiley Online, were used to fetch data on C. album. This review offers over up-to-date knowledge on nutritious values, phytochemical composition, volatile compounds, as well as health benefits of C. album. The ethnobotanical and ethnomedicinal uses of the plant in India and other parts of the world are deliberately discussed. Scrutinizing the reported literature on C. album reveals its powerful nutrient composition advantageous in the development of food products. The impact of various cooking and processing methods on the nutritional profile and bioavailability are discussed. The future perspectives with regards to the potential for food and nutraceutical products are critically addressed. This review proves the necessity of breakthrough research to investigate the pharmacology and safety of phytochemicals and nutraceutical development studies on the C. album.

Antiproliferative Activity and Impact on Human Gut Microbiota of New O-Alkyl Derivatives of Naringenin and Their Oximes

Naringenin is a 5,7,4′-trihydroxyflavanone naturally occurring mainly in citrus fruits, characterized by a wide spectrum of biological activity. Chemical modifications based on alkylation and oximation in most cases increase its bioactivity. The aim of our research was to evaluate the antiproliferative activity and influence on selected representatives of the human gut microbiota of new synthesized O-alkyl derivatives (A1–A10) and their oximes (B1–B10), which contain hexyl, heptyl, octyl, nonyl and undecyl chains attached to the C-7 or to both the C-7 and C-4′ positions in naringenin. To the best of our knowledge, compounds A3, A4, A6, A8–A10 and B3–B10 have not been described in the scientific literature previously. The anticancer activity was tested on human colon cancer cell line HT-29 and mouse embryo fibroblasts 3T3-L1 using the sulforhodamine B (SRB) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assays. We also determined the impacts of all compounds on the growth of Gram-positive and Gram-negative bacterial strains, such as Staphylococcus aureus, Enterococcus faecalis and Escherichia coli. The antimicrobial activity was expressed in terms of minimal inhibitory concentrations (MIC) and minimal bactericidal concentrations (MBC) values. For 7,4′-di-O-hexylnaringenin (A2), 7-O-undecylnaringenin (A9) and their oximes (B2, B9), which were safe for microbiota (MIC > 512 µg/mL) and almost all characterized by high cytotoxicity against the HT-29 cell line (A2: IC₅₀ > 100 µg/mL; A9: IC₅₀ = 17.85 ± 0.65 µg/mL; B2: IC₅₀ = 49.76 ± 1.63 µg/mL; B9: IC₅₀ = 11.42 ± 1.17 µg/mL), apoptosis assays were performed to elucidate their mechanisms of action. Based on our results, new compound B9 induced an apoptotic process via caspase 3/7 activation, which proved its potential as an anticancer agent.

Naringenin Microsphere as a Novel Adjuvant Reverses Colistin Resistance via Various Strategies against Multidrug-Resistant Klebsiella pneumoniae Infection

The efficacy of colistin, the last option against multidrug-resistant (MDR) Gram-negative bacteria, is severely threatened by the prevalence of plasmid- or chromosome-mediated colistin resistance genes. Herein, naringenin has dramatically restored colistin sensitivity against colistin-resistant Klebsiella pneumoniae infection without affecting bacterial viability, inducing resistance and causing obvious cell toxicity. Mechanism analysis reveals that naringenin potentiates colistin activity by multiple strategies including inhibition of mobilized colistin resistance gene activity, repression of two-component system regulation, and acceleration of reactive oxygen species-mediated oxidative damage. A lung-targeted delivery system of naringenin microspheres has been designed to facilitate naringenin bioavailability, accompanied by an effective potentiation of colistin for Klebsiella pneumoniae infection. Consequently, a new recognition of naringenin microspheres has been elucidated to restore colistin efficacy against colistin-resistant Gram-negative pathogens, which may be an effective strategy of developing potential candidates for MDR Gram-negative bacteria infection.

Effectiveness and safety research of Qingfei Paidu (QFPD) in treatment of COVID-19: an up-to-date systematic review and meta-analysis

Background

Since the outbreak of COVID-19 in 2019, the global economy, culture, politics, and people's lives and health have been severely damaged and threatened. Although western modern medical treatment has made great efforts, the treatment of COVID-19 has not achieved ideal clinical efficacy with severe sequelae. Qingfei Paidu (QFPD), an important herbal prescription for COVID-19 treatment, has shown remarkable therapeutic effects in China's fight against the epidemic.

Materials and methods

We searched seven databases up to 7 September 2022, including PubMed, Chinese National Knowledge Infrastructure (CNKI), Wanfang Database, Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE, World Scientific and SpringerLink. We used the Cochrane Risk of Bias tool to assess the quality of randomized controlled trials. All analysis results were conducted by RevMan 5.4.1 to carry out a meta-analysis.

Results

Fifteen studies with 10390 patients were included. QFPD could not only significantly improve the cure rate and lung CT of COVID-19, reduce the number of patients turning to critical condition and death, shorten the time for nucleic acid conversion and the length of hospital stay, but change laboratory indexes and relieve body symptoms quickly without adverse effects.

Conclusions

Compared with patients only treated by conventional western treatment (CWM), QFPD combined with CWM could be more effective for patients. It is worth spreading to other countries in the global battle against COVID-19.

Naringenin Alleviates Renal Ischemia Reperfusion Injury by Suppressing ER Stress-Induced Pyroptosis and Apoptosis through Activating Nrf2/HO-1 Signaling Pathway

Endoplasmic reticulum (ER) stress, pyroptosis, and apoptosis are critical molecular events in the occurrence and progress of renal ischemia reperfusion (I/R) injury. Naringenin (4′,5,7-trihydroxyflavanone) is one of the most widely consumed flavonoids with powerful antioxidant and anti-inflammatory activities. However, whether naringenin is able to relieve renal I/R injury and corresponding mechanisms have not been fully clarified. This study was aimed at exploring its role and relevant mechanisms in renal I/R injury. The C57Bl/6 mice were randomly assigned to receive administration with naringenin (50 mg/kg/d) or sterile saline (1.0 mL/d) for 3 d by gavage and suffered from renal I/R surgery. One specific ER stress inhibitor, 4-phenylbutyric acid (4-PBA, 100 mg/kg/d), was intraperitoneally administered to validate the regulation of ER stress on pyroptosis and apoptosis. Cultured HK-2 cells went through the process of hypoxia/reoxygenation (H/R) to perform cellular experiments with the incubation of naringenin (200 μM), 4-PBA (5 mM), or brusatol (400 nM). The animal results verified that naringenin obviously relieved renal I/R injury, while it refined renal function and attenuated tissue structural damage. Furthermore, naringenin treatment inhibited I/R-induced ER stress as well as pyroptosis and apoptosis as indicated by decreased levels of specific biomarkers such as GRP78, CHOP, caspase-12, NLRP3, ASC, caspase-11, caspase-4, caspase-1, IL-1β, GSDMD-N, BAX, and cleaved caspase-3 in animals and HK-2 cells. Besides, the upregulated expression of Nrf2 and HO-1 proteins after naringenin treatment suggested that naringenin activated the Nrf2/HO-1 signaling pathway, which was again authenticated by the usage of brusatol (Bru), one unique inhibitor of the Nrf2 pathway. Importantly, the application of 4-PBA showed that renal I/R-generated pyroptosis and apoptosis were able to be regulated by ER stress in vivo and in vitro. In conclusion, naringenin suppressed ER stress by activating Nrf2/HO-1 signaling pathway and further alleviated pyroptosis and apoptosis to protect renal against I/R injury.

Molecular Mechanistic Pathways Targeted by Natural Compounds in the Prevention and Treatment of Diabetic Kidney Disease

Diabetic kidney disease (DKD) is one of the most common complications of diabetes, and its prevalence is still growing rapidly. However, the efficient therapies for this kidney disease are still limited. The pathogenesis of DKD involves glucotoxicity, lipotoxicity, inflammation, oxidative stress, and renal fibrosis. Glucotoxicity and lipotoxicity can cause oxidative stress, which can lead to inflammation and aggravate renal fibrosis. In this review, we have focused on in vitro and in vivo experiments to investigate the mechanistic pathways by which natural compounds exert their effects against the progression of DKD. The accumulated and collected data revealed that some natural compounds could regulate inflammation, oxidative stress, renal fibrosis, and activate autophagy, thereby protecting the kidney. The main pathways targeted by these reviewed compounds include the Nrf2 signaling pathway, NF-κB signaling pathway, TGF-β signaling pathway, NLRP3 inflammasome, autophagy, glycolipid metabolism and ER stress. This review presented an updated overview of the potential benefits of these natural compounds for the prevention and treatment of DKD progression, aimed to provide new potential therapeutic lead compounds and references for the innovative drug development and clinical treatment of DKD.