Bioactivity-guided isolation of the major anthocyanin from Lycium ruthenicum Murr. fruit and its antioxidant activity and neuroprotective effects in vitro and in vivo

Protective effect and mechanism of Lycium ruthenicum Murray anthocyanins against retinal damage induced by blue light exposure

Lycium ruthenicum Murray (LR) is a medicine and edible plant in Northwest China, and L. ruthenicum Murray anthocyanins (LRA) are green antioxidants with various pharmacological activities, such as antioxidant and anti-inflammatory activities. However, the protective effect and mechanism of LRA against retinal damage induced by blue light exposure are poorly understood. This study explored the protective effects and potential mechanisms of LRA on retinal damage induced by blue light exposure in vitro and in vivo. The results showed that LRA could ameliorate oxidative stress injury by activating the antioxidant stress nuclear factor-related factor 2 pathway, promoting the expression of phase II detoxification enzymes (HO-1, NQO1) and endogenous antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase), and reducing reactive oxygen species and malondialdehyde levels. Additionally, LRA could inhibit inflammatory response by decreasing the expression of blue light exposure-induced nuclear factor-κB (NF-κB) pathway-related proteins (NF-κB and p-IκBα), as well as interleukin (IL)-6, tumor necrosis factor-α, IL-1β pro-inflammatory factors and pro-inflammatory chemokine VEGF, and increasing the expression of anti-inflammatory factor IL-10. Furthermore, LRA could ameliorate oxidative stress-induced apoptosis by upregulating Bcl-2 and downregulating Bax and Caspase-3 protein expression. All these results indicate that LRA can be used as an antioxidant dietary supplement for the treatment or prevention of retinal diseases.

The Medicinal Species of the Lycium Genus (Goji Berries) in East Asia: A Review of Its Effect on Cell Signal Transduction Pathways

Natural plants contain numerous chemical compounds that are beneficial to human health. The berries from the Lycium genus are widely consumed and are highly nutritious. Moreover, their chemical constituents have attracted attention for their health-promoting properties. In East Asia, there are three varieties of the Lycium genus (Lycium barbarum L., Lycium chinense Miller, and L. ruthenicum Murray) that possess medicinal value and are commonly used for treating chronic diseases and improving metabolic disorders. These varieties are locally referred to as "red Goji berries" or "black Goji berries" due to their distinct colors, and they differ in their chemical compositions, primarily in terms of carotenoid and anthocyanin content. The pharmacological functions of these berries include anti-aging, antioxidant, anti-inflammatory, and anti-exercise fatigue effects. This review aims to analyze previous and recent studies on the active ingredients and pharmacological activities of these Lycium varieties, elucidating their signaling pathways and assessing their impact on the gut microbiota. Furthermore, the potential prospects for using these active ingredients in the treatment of COVID-19 are evaluated. This review explores the potential targets of these Lycium varieties in the treatment of relevant diseases, highlighting their potential value in drug development.

Anthocyanin biosynthesis in goji berry is inactivated by deletion in a bHLH transcription factor LrLAN1b promoter

Black goji berry (Lycium ruthenicum Murray) contains a rich source of health-promoting anthocyanins which are used in herbal medicine and nutraceutical foods in China. A natural variant producing white berries allowed us to identify two key genes involved in the regulation of anthocyanin biosynthesis in goji berries: one encoding a MYB transcription factor (LrAN2-like) and one encoding a basic helix-loop-helix (bHLH) transcription factor (LrAN1b). We previously found that LrAN1b expression was lost in the white berry variant, but the molecular basis for this phenotype was unknown. Here, we identified the molecular mechanism for loss of anthocyanins in white goji berries. In white goji, the LrAN1b promoter region has a 229 bp deletion that removes three MYB-binding elements and one bHLH-binding element, which are key to its expression. Complementation of the white goji berry LrAN1b allele with the LrAN1b promoter restored pigmentation. Virus-induced gene silencing of LrAN1b in black goji berry reduced fruit anthocyanin biosynthesis. Molecular analyses showed that LrAN2-like and another bHLH transcription factor LrJAF13 can activate LrAN1b by binding directly to the MYB-recognizing element and bHLH-recognizing element of its promoter-deletion region. LrAN1b expression is enhanced by the interaction of LrAN2-like with LrJAF13 and the WD40 protein LrAN11. LrAN2-like and LrAN11 interact with either LrJAF13 or LrAN1b to form two MYB-bHLH-WD40 complexes, which hierarchically regulate anthocyanin biosynthesis in black goji berry. This study on a natural variant builds a comprehensive anthocyanin regulatory network that may be manipulated to tailor goji berry traits.

Bioactive Components in Fruit Interact with Gut Microbes

Fruits contain many bioactive compounds, including polysaccharides, oligosaccharides, polyphenols, anthocyanins, and flavonoids. All of these bioactives in fruit have potentially beneficial effects on gut microbiota and host health. On the one hand, fruit rich in active ingredients can act as substrates to interact with microorganisms and produce metabolites to regulate the gut microbiota. On the other hand, gut microbes could promote health effects in the host by balancing dysbiosis of gut microbiota. We have extensively analyzed significant information on bioactive components in fruits based on Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Although the deep mechanism of action of bioactive components in fruits on gut microbiota needs further study, these results also provide supportive information on fruits as a source of dietary active ingredients to provide support for the adjunctive role of fruits in disease prevention and treatment.

Black Goji Berry (Lycium ruthenicum Murray): A Review of Its Pharmacological Activity

Lycium ruthenicum Murray (LRM; commonly known as black goji berry or black wolfberry), a plant in the Solanaceae family, grows in the deserts of China's Qinghai-Tibet plateau. LRM is widely consumed in traditional Chinese medicine, and its fruits are frequently used as herbal remedies to treat heart disease, fatigue, inflammation, and other conditions. Many studies have reported that LRM is rich in functional phytochemicals, such as anthocyanins and polysaccharides, and has various pharmacological actions. This article reviews research on the biological and pharmacological effects of the constituents of LRM fruits. LRM has various pharmacological properties, such as antioxidant, anti-inflammatory, anti-radiation, immune-enhancing, anti-tumor, and protective effects. LRM has much promise as a dietary supplement for preventing many types of chronic metabolic disease.

Polyphenolic glycosides with unusual four-membered ring possessing anti-Parkinson's disease potential from black wolfberry

This work reports the isolation of seven undescribed polyphenolic glycosides (1-7) together with fourteen known compounds (8-21) from the fruit of Lycium ruthenicum Murray. The structures of the undescribed compounds were identified based on comprehensive spectroscopic methods including IR, HRESIMS, NMR and ECD, and chemical hydrolysis. Compounds 1-3 possess an unusual four-membered ring, while 11-15 were firstly isolated from this fruit. Interestingly, compounds 1-3 inhibited monoamine oxidase B with IC₅₀ of 25.36 ± 0.44, 35.36 ± 0.54, and 25.12 ± 1.59 μM, respectively, and showed significant neuroprotective effect on PC12 cells injured by 6-OHDA. Moreover, compound 1 improved the lifespan, dopamine level, climbing behaviour, and olfactory ability of the PINK1^B9 flies, a Drosophila model of Parkinson's disease. This work presents the first in vivo neuroprotective evidence of the small molecular compounds in L. ruthenicum Murray fruit, indicating its good potential as neuroprotectant.

Cyanidin-3-O-glucoside and protocatechuic acid alleviate heat stress-induced testicular damage

Testicular hyperthermia induced by unhealthy living habits and pathological or occupational factors can cause spermatogenic dysfunction with an outcome of sub-fertility or even infertility. Cyanidin-3-O-glucoside (C3G) is the most typical anthocyanin in foods that has been recognized as an antioxidant with promising protection for male reproduction. However, its specific effect against testicular hyperthermia and the mechanisms involving its primary gastrointestinal metabolite protocatechuic acid (PCA) are still unexplored. In the present study, testicular hyperthermia in mice was established by employing a single hot water bath at 43 °C for 30 min. C3G and PCA were intragastrically given to investigate their prevention ability against heat stress-induced testicular damage. It was found that C3G and PCA restored the external diameter and thickness, and alleviated atrophy and vacuolation of seminiferous tubules. Simultaneously, C3G and PCA enhanced testicular heat stress tolerance through reducing superfluous eIF2α phosphorylation and stress granule formation. C3G and PCA effectively improved the testicular antioxidant system and regulated the IRE1α-XBP1 pathway, contributing to mitigatory spermatogenesis dysfunction and testicular damage. This finding revealed that anthocyanins were the novel compounds for alleviating testicular damage, and provided a reliable theoretical basis for improving male fertility disturbed by heat stress.

Anthocyanins in Plant Food: Current Status, Genetic Modification, and Future Perspectives

Anthocyanins are naturally occurring polyphenolic pigments that give food varied colors. Because of their high antioxidant activities, the consumption of anthocyanins has been associated with the benefit of preventing various chronic diseases. However, due to natural evolution or human selection, anthocyanins are found only in certain species. Additionally, the insufficient levels of anthocyanins in the most common foods also limit the optimal benefits. To solve this problem, considerable work has been done on germplasm improvement of common species using novel gene editing or transgenic techniques. This review summarized the recent advances in the molecular mechanism of anthocyanin biosynthesis and focused on the progress in using the CRISPR/Cas gene editing or multigene overexpression methods to improve plant food anthocyanins content. In response to the concerns of genome modified food, the future trends in developing anthocyanin-enriched plant food by using novel transgene or marker-free genome modified technologies are discussed. We hope to provide new insights and ideas for better using natural products like anthocyanins to promote human health.

Pesticides as a risk factor for cognitive impairment: Natural substances are expected to become alternative measures to prevent and improve cognitive impairment

Pesticides are the most effective way to control diseases, insects, weeds, and fungi. The central nervous system (CNS) is damaged by pesticide residues in various ways. By consulting relevant databases, the systemic relationships between the possible mechanisms of pesticides damage to the CNS causing cognitive impairment and related learning and memory pathways networks, as well as the structure-activity relationships between some natural substances (such as polyphenols and vitamins) and the improvement were summarized in this article. The mechanisms of cognitive impairment caused by pesticides are closely related. For example, oxidative stress, mitochondrial dysfunction, and neuroinflammation can constitute three feedback loops that interact and restrict each other. The mechanisms of neurotransmitter abnormalities and intestinal dysfunction also play an important role. The connection between pathways is complex. NMDAR, PI3K/Akt, MAPK, Keap1/Nrf2/ARE, and NF-κB pathways can be connected into a pathway network by targets such as Ras, Akt, and IKK. The reasons for the improvement of natural substances are related to their specific structure, such as polyphenols with different hydroxyl groups. This review's purpose is to lay a foundation for exploring and developing more natural substances that can effectively improve the cognitive impairment caused by pesticides.

Association between Dietary Total Antioxidant Capacity of Antioxidant Vitamins and the Risk of Stroke among US Adults

The intake of antioxidant vitamins can scavenge free radicals and reduce oxidative stress, which may be beneficial for stroke. However, the relationship between total antioxidant capacity (TAC) of antioxidant vitamins and stroke is controversial. This study aims to investigate the association between dietary TAC and the risk of stroke in US adults. This study included participants over 20 years old from the 2001-2018 National Health and Nutrition Examination Survey (NHANES). Data from two 24 h dietary recalls were used to estimate the usual intake of antioxidant vitamins. TAC was calculated by the vitamin C equivalent antioxidant capacity reference values of individual antioxidant vitamins. Survey-weighted generalized linear models were performed to evaluate the relationship between TAC and the risk of stroke. A restricted cubic spline regression model was used to investigate the dose-response association. A total of 37,045 participants was involved, of whom 1391 suffered a stroke. Compared with the first tertile, the participants in the second tertile of TAC showed a lower risk of stroke (OR = 0.788, 95% CI: 0.662, 0.936) after adjusting for potential risk factors. The dose-response analysis showed a gradual increase in the risk of stroke as TAC decreases. Subgroups analyses indicated that this association was primarily in the population of those aged over 60 years old, who were female, consumed alcohol, were a former smoker and inactive. The sensitivity analysis presented consistent results. These results suggest that deficiency of dietary TAC was associated with an increased risk of stroke, particularly in populations with underlying oxidative stress injury.

Heterocyclic aromatic amines induce Neuro-2a cells cytotoxicity through oxidative stress-mediated mitochondria-dependent apoptotic signals

Heterocyclic aromatic amines (HAAs) are a class of hazardous compounds produced in food thermal processing. These compounds raise concerns because they have mutagenic and carcinogenic properties. However, the neurotoxicity of these compounds has received limited attention. Here, the toxic effects of three HAAs, i.e. 9H-pyrido[3,4-b]indole (Norharman), 1-methyl-9H-pyrido[3,4-b]indole (Harman), and 2-amino-3-methylimidazole[4,5-f]quinoline (IQ) were investigated in Neuro-2a cells model. The results showed that the survival rate of cells decreased in a dose-dependent manner and apoptosis occurred after exposure to the three HAAs for 24 h and 48 h. Their neurotoxicity was ranked as Harman > Norharman > IQ. Further, treatment of Harman, Norharman, or IQ at 50 and 100 μM for 48 h led to intracellular REDOX imbalance, which was manifested as increased ROS and malondialdehyde (MDA) levels, decreased GSH/GSSG ratio, and reduced SOD and CAT activities. Moreover, Norharman and Harman up-regulated the expression level of nuclear factor erythroid 2-related factor 2 (Nrf2), as well as the mRNA levels of Heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoredutase1 (NQO1), while IQ had no significant effect on the levels of Nrf2, HO-1, and NQO1. Additionally, Harman, Norharman, or IQ exposure significantly reduced mitochondrial membrane potential and intracellular ATP levels and up-regulated the levels of apoptosis-related genes and proteins. Collectively, our finding suggested that HAAs were neurotoxic, with mechanisms related to induction of oxidative stress and mitochondrial dysfunction.

Insight into the Progress on Natural Dyes: Sources, Structural Features, Health Effects, Challenges, and Potential

(1) Background: Dyes play an important role in food, medicine, textile, and other industries, which make human life more colorful. With the increasing demand for food safety, the development of natural dyes becomes more and more attractive. (2) Methods: The literature was searched using the electronic databases PubMed, Web of Science, and SciFinder and this scoping review was carried out following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). (3) Results: 248 articles were included in this review. This review summarizes the research progress on natural dyes in the last ten years. According to structural features, natural dyes mainly include carotenoids, polyphenols, porphyrins, and alkaloids, and some of the newest dyes are summarized. Some pharmacological activities of carotenoids, anthocyanin, curcumin, and betalains in the last 10 years are summarized, and the biological effects of dyes regarding illumination conditions. The disadvantages of natural dyes, including sources, cost, stability, and poor bioavailability, limit their application. Here, some feasible strategies (potential resources, biotechnology, new extraction and separation strategies, strategies for improving stability) are described, which will contribute to the development and utilization of natural dyes. (4) Conclusion: Natural dyes show health benefits and potential in food additives. However, it is necessary for natural dyes to pass toxicity tests and quality tests and receive many regulatory approvals before their final entry into the market as food colorants or as drugs.