The role of flavonoids in autoimmune diseases: Therapeutic updates

Role of polyphenolics in the management of rheumatoid arthritis through intracellular signaling pathways: a mechanistic review

Inflammation of the joints, bone erosion, and cartilage destruction are the main characteristics of rheumatoid arthritis (RA) which causes joint malfunction, structural distortion, and long-term impairment of function. According to various studies, RA affects 0.1-2.0% of people globally. It is unclear what causes RA, but multiple pathways have been associated with its pathophysiology. Non-steroidal anti-inflammatory drugs; NSAIDs (diclofenac, celecoxib, and ibuprofen), disease-modifying antirheumatic drugs; DMARDs (methotrexate, azathioprine, and cyclosporine), immunological compounds (rituximab, anakinra, and infliximab), and immune suppressants are the currently available options. However, they are associated with major side effects, like hypertension, hepatotoxicity, gastric ulcers, and kidney dysfunction which results in their limited use. To treat RA effectively, there is an urgent need for treatment options that offer minimal side effects. The dietary polyphenols have therapeutic effects on RA based on their antioxidant, apoptotic, anti-inflammatory, immunosuppressive, and immunomodulatory characteristics. At the molecular level, interleukin (IL)-6, mitogen-activated protein kinase (MAPK), tumor necrosis factor-alpha (TNF-alpha), interleukin 1b, c-Jun N-terminal kinase (JNK), and nuclear factor k light-chain-enhancer of activated B-cell (NF-kB) pathways play a critical role in modulation. Various polyphenolic compounds have been studied for their potential efficacy against RA, including genistein, resveratrol, carnosol, curcumin, epigallocatechin gallate, kaempferol, and hydroxyl tyrosol. However, it is noted that most of the studies are investigated on animal models of RA. The present review article discusses the underlying mechanisms that lead to RA and explores the promising role of polyphenols as potential therapeutic agents.

Flavonoid Supplementation Is Beneficial for Polycystic Ovary Syndrome: A Systematic Review and Meta-analysis

CONTEXT

Polycystic ovary syndrome (PCOS) is a prevalent hormonal imbalance that predominantly affects women in their reproductive years. Previous studies have yielded conflicting conclusions.

OBJECTIVE

This is an updated meta-analysis aiming to explore the connection between flavonoid supplementation and PCOS.

DATA SOURCES

Seven databases were searched: Cochrane Library, PubMed, Web of Science, Embase, Wanfang, China Science and Technology Journal, and China National Knowledge Infrastructure, spanning from their inception to April 15, 2024.

DATA EXTRACTION

Two authors independently searched the databases using the search terms.

DATA ANALYSIS

Following strict inclusion criteria, 8 papers were ultimately included. This updated meta-analysis suggests that flavonoid supplementation could enhance follicular development, promote the proliferation and differentiation of follicular granulosa cells, elevate estradiol levels, and mitigate testosterone, C-reactive protein, and ovarian index levels.

CONCLUSION

This analysis suggests that dietary flavonoids could potentially alleviate symptoms associated with PCOS.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42022382912.

Emerging Phytochemical Formulations for Management of Rheumatoid Arthritis: A Review

Rheumatoid arthritis (RA) is a T-cell-mediated chronic inflammatory disorder affecting 0.5-1% of the global population. The disease with unknown etiology causes slow destruction of joints, advancing to significant deterioration of an individual's quality of life. The present treatment strategy comprises the use of disease-modifying anti-rheumatic drugs (DMARDs) coupled with or without nonsteroidal anti-inflammatory drugs or glucocorticoids. Additionally, involves co-therapy of injectable biological DMARDs in case of persistent or recurrent arthritis. The availability of biological DMARDs and the implementation of the treat-to-target approach have significantly improved the outcomes for patients suffering from RA. Nevertheless, RA requires continuous attention due to inadequate response of patients, development of tolerance and severe side effects associated with long-term use of available treatment regimens. An estimated 60-90% of patients use alternative methods of treatment, such as herbal therapies, for the management of RA symptoms. Over the past few decades, researchers have exploring natural phytochemicals to alleviate RA and associated symptoms. Enormous plant-origin phytochemicals such as alkaloids, flavonoids, steroids, terpenoids and polyphenols have shown anti-inflammatory and immunomodulatory activity against RA. However, phytochemicals have certain limitations, such as high molecular weight, poor water solubility, poor permeability, poor stability and extensive first-pass metabolism, limiting absorption and bioavailability. The use of nanotechnology has aided to extensively improve the pharmacokinetic profile and stability of encapsulated drugs. The current review provides detailed information on the therapeutic potential of phytochemicals. Furthermore, the review focuses on developed phytochemical formulations for RA, with emphasis on clinical trials, regulatory aspects, present challenges, and future prospects.

Association between flavonoid intake and rheumatoid arthritis among US adults

Basic research shows that flavonoids have anti-inflammatory effects that influence rheumatoid arthritis (RA) in rats. Investigating potential dietary interventions for RA helps prevent the onset and progression of the disease. Clinical evidence on the association of flavonoid and subclass intake with RA is lacking. Using three survey cycles of 2007-2008, 2009-2010, and 2017-2018 from the National Health and Nutrition Survey and the United States Department of Agriculture's Food and Nutrient Database for Dietary Studies (FNDDS), we analyzed 7,419 American adults (≥20 years old). The values of flavonoid and subclass intake were calculated using FNDDS. The status questions for self-reported RA were from the NHANES codebook. Weighted analyses, revealed that among the 7,419 participants included in this study (mean age of 44.69 years [standard error, 0.40] and 3,584 [48.31%] were female), 408 met the classification criteria for RA. According to the multivariable logistic regression model, compared with the risk of RA in the first quartile (Q1), the risks of RA in the second quartile (Q2), the third quartile (Q3) and the fourth quartile (Q4) were lower (Q2: OR=0.55, 95% CI: 0.38-0.80; Q3: OR=0.66, 95% CI: 0.44-0.97; Q4: OR=0.64, 95% CI: 0.46-0.89; trend: P=.03). The association between total flavonoids and RA remained significant after full consideration of confounding factors. With regard to the subclasses of flavonoids, high flavanones intake was associated with low RA prevalence in Model 3 (Q3: OR= 0.60, 95% CI:0.39-0.92; Q4: OR = 0.56, 95% CI: 0.32-0.99, trend: P=.02), but no such association was found in the other subclasses. Total flavonoids intake protected against RA, and the risk of developing RA decreased significantly with increasing intake of total flavonoids. Total flavonoids and flavanones were significantly associated with reduced RA risk for the American adult population. We highlighted the importance of employing diverse methodologies to assess the health effects of flavonoids.

The treatment of psoriasis via herbal formulation and nano-polyherbal formulation: A new approach

Psoriasis is a chronic condition that can strike at any age. This sickness is associated with inflammatory problems that impact all humans in the world. Psoriasis is more common in Scandinavians than in Asian and African populations due to a combination of factors such as age, gender, geographic location, ethnicity, genetic and environmental factors. Immune stimulation, genetic contribution, antimicrobial peptides, and other significant triggers such as medicines, immunizations, infections, trauma, stress, obesity, alcohol intake, smoking, air pollution, sun exposure, and particular disorders cause psoriasis. Numerous clinical research investigations are now underway, and therapeutic alternatives are available. However, these therapies only improve symptoms and do not accomplish a complete cure; they also have dangerous and undesirable side effects. Natural products have gained popularity recently due to their great effectiveness, safety, and low toxicity. Natural formulations of various nanocarriers like liposomes, lipospheres, nanogels, emulgel, nanostructured lipid carriers, nanosponge, nanofibers, niosomes, nanomiemgel, nanoemulsions, nanospheres, cubosomes, microneedles, nanomicelles, ethosomes, nanocrystals, and foams, have significantly contributed and encouraged advancement in psoriasis disease treatment. These phytochemical-loaded new nanoformulations address several issues associated with natural products in conventional dosage forms, such as instability, poor solubility, and limited bioavailability. This article reviews some of the intriguing phytochemicals, as well as their possible molecular target locations and mechanisms of action, which may assist in the development of more specific and selective antipsoriatic medicines. Exploring and understanding phytochemicals' functions will allow for more site-specific psoriasis treatment techniques. This review concluded the psoriasis disease with phytoconstituent loaded herbal or polyherbal nanocarriers and their mechanistic approach.

Exploring the Therapeutic Potential of Natural Compounds in Psoriasis and Their Inclusion in Nanotechnological Systems

Psoriasis is a chronic inflammatory disease that affects around 2-3% of the world's population. The treatment for this autoimmune disease still remains centered around conventional methods using synthetic substances, even though more recent advancements focus on biological therapies. Given the numerous side effects of such treatments, current research involves plant extracts and constituents that could prove useful in treating psoriasis. The aim of this narrative review is to highlight the most known representatives belonging to classes of natural compounds such as polyphenols (e.g., astilbin, curcumin, hesperidin, luteolin, proanthocyanidins, and resveratrol), alkaloids (e.g., berberine, capsaicin, and colchicine), coumarins (psoralen and 8-methoxypsoralen), and terpenoids (e.g., celastrol, centelloids, and ursolic acid), along with plants used in traditional medicine that could present therapeutic potential in psoriasis. The paper also provides an overview of these compounds' mechanisms of action and current inclusion in clinical studies, as well as an investigation into their potential incorporation in various nanotechnological systems, such as lipid-based nanocarriers or polymeric nanomaterials, that may optimize their efficacy during treatment.

Polyphenols as Potential Geroprotectors

Significance: Currently, a large amount of evidence of beneficial effects of diets enriched with polyphenols on various aspects of health has been accumulated. These phytochemicals have a geroprotective potential slowing down the pathological processes associated with aging and ensuring longevity. In this study, a comprehensive analysis was conducted to determine the adherence of individual polyphenols to geroprotector criteria. Data from experimental models, clinical trials, and epidemiological studies were analyzed. Recent Advances: Sixty-two polyphenols have been described to increase the life span and improve biomarkers of aging in animal models. They act via evolutionarily conserved molecular mechanisms, including hormesis and maintenance of redox homeostasis, epigenetic regulation, response to cellular damage, metabolic control, and anti-inflammatory and senolytic activity. Epidemiological and clinical studies suggest that certain polyphenols have a potential for prevention and treatment of various diseases, including cancer, metabolic disorders, and cardiovascular conditions in humans. Critical Issues: Among the reviewed phytochemicals, chlorogenic acid, quercetin, epicatechin, genistein, resveratrol, and curcumin were identified as compounds with the highest geroprotective potential. However, there is a lack of unambiguous information on the effectiveness and safety of polyphenols for increasing health span, preventing and treating aging-associated diseases in humans. Future Directions: Further research is needed to fully understand the effects of polyphenols considering their long-term consumption, metabolic modification and bioavailability, complex interactions between different groups of polyphenols and with other phytochemicals, as well as their effects on individuals with different health status. Antioxid. Redox Signal. 40, 564-593.

The Promising Role of Polyphenols in Skin Disorders

The biochemical characteristics of polyphenols contribute to their numerous advantageous impacts on human health. The existing research suggests that plant phenolics, whether consumed orally or applied directly to the skin, can be beneficial in alleviating symptoms and avoiding the development of many skin disorders. Phenolic compounds, which are both harmless and naturally present, exhibit significant potential in terms of counteracting the effects of skin damage, aging, diseases, wounds, and burns. Moreover, polyphenols play a preventive role and possess the ability to delay the progression of several skin disorders, ranging from small and discomforting to severe and potentially life-threatening ones. This article provides a concise overview of recent research on the potential therapeutic application of polyphenols for skin conditions. It specifically highlights studies that have investigated clinical trials and the use of polyphenol-based nanoformulations for the treatment of different skin ailments.

Role of bio-flavonols and their derivatives in improving mitochondrial dysfunctions associated with pancreatic tumorigenesis

Mitochondria, a cellular metabolic center, efficiently fulfill cellular energy needs and regulate crucial metabolic processes, including cellular proliferation, differentiation, apoptosis, and generation of reactive oxygen species. Alteration in the mitochondrial functions leads to metabolic imbalances and altered extracellular matrix dynamics in the host, utilized by solid tumors like pancreatic cancer (PC) to get energy benefits for fast-growing cancer cells. PC is highly heterogeneous and remains unidentified for a longer time because of its complex pathophysiology, retroperitoneal position, and lack of efficient diagnostic approaches, which is the foremost reason for accounting for the seventh leading cause of cancer-related deaths worldwide. PC cells often respond poorly to current therapeutics because of dense stromal barriers in the pancreatic tumor microenvironment, which limit the drug delivery and distribution of antitumor immune cell populations. As an alternative approach, various natural compounds like flavonoids are reported to possess potent antioxidant and anticancerous properties and are less toxic than current chemotherapeutic drugs. Therefore, we aim to summarize the current state of knowledge regarding the pharmacological properties of flavonols in PC in this review from the perspective of mitigating mitochondrial dysfunctions associated with cancer cells. Our literature survey indicates that flavonols efficiently regulate cellular metabolism by scavenging reactive oxygen species, mitigating inflammation, and arresting the cell cycle to promote apoptosis in tumor cells via intrinsic mitochondrial pathways. In particular, flavonols proficiently inhibit the cancer-associated proliferation and inflammatory pathways such as EGFR/MAPK, PI3K/Akt, and nuclear factor κB in PC. Overall, this review provides in-depth evidence about the therapeutic potential of flavonols for future anticancer strategies against PC; still, more multidisciplinary human interventional studies are required to dissect their pharmacological effect accurately.

The Antidiabetic Mechanisms of Hesperidin: Hesperidin Nanocarriers as Promising Therapeutic Options for Diabetes

A natural flavonoid with exceptional medicinal capabilities, hesperidin, has shown encouraging results in the treatment of diabetes. Thoughts are still being held on the particular processes through which hesperidin exerts its anti-diabetic effects. This work clarifies the complex antidiabetic mechanisms of hesperidin by investigating the molecular pathways involved in glucose homeostasis, insulin signaling, and oxidative stress control. Additionally, the article explores the newly developing field of nanocarrier-based systems as a prospective means of boosting the therapeutic efficiency of hesperidin in the treatment of diabetes. This is because there are difficulties connected with the efficient delivery of hesperidin. These cutting-edge platforms show enormous potential for changing diabetes therapy by utilizing the benefits of nanocarriers, such as enhanced solubility, stability, and targeted delivery. In conclusion, our comprehensive review emphasizes the antidiabetic potential of hesperidin and underscores the intriguing possibilities provided by hesperidin nanocarriers in the search for more effective and individualized diabetes therapies.

Antiviral Flavonoids: A Natural Scaffold with Prospects as Phytomedicines against SARS-CoV2

Flavonoids are vital candidates to fight against a wide range of pathogenic microbial infections. Due to their therapeutic potential, many flavonoids from the herbs of traditional medicine systems are now being evaluated as lead compounds to develop potential antimicrobial hits. The emergence of SARS-CoV-2 caused one of the deadliest pandemics that has ever been known to mankind. To date, more than 600 million confirmed cases of SARS-CoV2 infection have been reported worldwide. Situations are worse due to the unavailability of therapeutics to combat the viral disease. Thus, there is an urgent need to develop drugs against SARS-CoV2 and its emerging variants. Here, we have carried out a detailed mechanistic analysis of the antiviral efficacy of flavonoids in terms of their potential targets and structural feature required for exerting their antiviral activity. A catalog of various promising flavonoid compounds has been shown to elicit inhibitory effects against SARS-CoV and MERS-CoV proteases. However, they act in the high-micromolar regime. Thus a proper leadoptimization against the various proteases of SARS-CoV2 can lead to high-affinity SARS-CoV2 protease inhibitors. To enable lead optimization, a quantitative structure-activity relationship (QSAR) analysis has been developed for the flavonoids that have shown antiviral activity against viral proteases of SARS-CoV and MERS-CoV. High sequence similarities between coronavirus proteases enable the applicability of the developed QSAR to SARS-CoV2 proteases inhibitor screening. The detailed mechanistic analysis of the antiviral flavonoids and the developed QSAR models is a step forward toward the development of flavonoid-based therapeutics or supplements to fight against COVID-19.

Naringin may promote functional recovery following spinal cord injury by modulating microglial polarization through the PPAR-γ/NF-κB signaling pathway

OBJECTIVE

The flavonoid Naringin (Nar) has been extensively investigated and found to have multiple pharmacological properties, including neuroprotection. Although recent reports have shown that Nar can effectively treat spinal cord injury (SCI), its potential mechanism remains unknown. This study aimed to investigate the effects of Nar on motor recovery and inflammatory responses after SCI and to elucidate its mechanism.

METHODS

SCI rat models were established using Allen's weight-drop method. The rats were intragastrically given Nar (40 mg/kg) for 21 d, and their motor function before surgery and on the 1st, 3rd, 7th, 14th, 21st days after surgery was assessed by the Basso-Beattie-Bresnahan (BBB) scale and examined by the grid walking test (GWT). The enzyme linked immunosorbent assay (ELISA) was used to detect the interleukin (IL)-1β, tumor necrosis factor (TNF)-α, and monocyte chemoattractant protein (MCP)-1 levels in rat spinal cord tissues, and quantitative reverse transcription polymerase chain reaction (qRT-PCR) to measure the mRNA expression levels of microglial activation markers CD68 and ionized calcium binding adaptor molecule 1 (Iba-1), M1 markers inducible nitric oxide synthase (iNOS) and IL-6, and M2 markers CD206 and Arginase 1 (Arg1). The expression levels of peroxisome proliferator-activated receptor gamma/nuclear factor kappa B (PPAR-γ/NF-κB) pathway-related proteins in rat spinal cord tissues were determined using western blotting.

RESULTS

Nar significantly increased the BBB score and decreased the mean error rate of GWT in SCI rats. Additionally, Nar effectively inhibited microglial activation and expression of M1 markers in spinal cord tissues. It also elevated M2 polarization-related gene expression and significantly lowered the levels of inflammatory factors. Further investigation showed that Nar enhanced the expression of PPAR-γ protein and inhibited NF-κB pathway activity.

CONCLUSION

Nar promotes functional recovery by regulating microglial polarization and inhibiting the inflammatory response in SCI, and its mechanism may be related to the PPAR-γ/NF-κB signaling pathway activity.

Therapeutic potential of natural products in inflammation: underlying molecular mechanisms, clinical outcomes, technological advances, and future perspectives

Chronic inflammation is a common underlying factor in many major diseases, including heart disease, diabetes, cancer, and autoimmune disorders, and is responsible for up to 60% of all deaths worldwide. Metformin, statins, and corticosteroids, and NSAIDs (non-steroidal anti-inflammatory drugs) are often given as anti-inflammatory pharmaceuticals, however, often have even more debilitating side effects than the illness itself. The natural product-based therapy of inflammation-related diseases has no adverse effects and good beneficial results compared to substitute conventional anti-inflammatory medications. In this review article, we provide a concise overview of present pharmacological treatments, the pathophysiology of inflammation, and the signaling pathways that underlie it. In addition, we focus on the most promising natural products identified as potential anti-inflammatory therapeutic agents. Moreover, preclinical studies and clinical trials evaluating the efficacy of natural products as anti-inflammatory therapeutic agents and their pragmatic applications with promising outcomes are reviewed. In addition, the safety, side effects and technical barriers of natural products are discussed. Furthermore, we also summarized the latest technological advances in the discovery and scientific development of natural products-based medicine.

Bioactive compounds in cruciferous sprouts and microgreens and the effects of sulfur nutrition

Cruciferous sprouts and microgreens are a good source of bioactive compounds for human health as they are rich in glucosinolates, polyphenols, carotenoids, and vitamins. Glucosinolates - sulfur-containing bioactive phytochemicals - have anti-cancer effects. They mainly exist in cruciferous vegetables. Sulfur is one of the essential elements for plants and is an indispensable component of glucosinolates. This paper summarizes the nutritional value of cruciferous spouts and microgreens, along with the effects of sulfur nutrition on bioactive phytochemical compounds of cruciferous sprouts and microgreens, especially glucosinolates, with the aim of providing information about the dietary effects of cruciferous sprouts and microgreens. © 2023 Society of Chemical Industry.

Mesoporous silica-based nanocarriers with dual response to pH and ROS for enhanced anti-inflammation therapy of 5-demethylnobiletin against psoriasis-like lesions

Psoriasis is an inflammatory skin disease accompanied with chronic papulosquamous lesions and multiple comorbidities that considerably affect patients' quality of life. In order to develop an enhanced therapeutic strategy for psoriasis, 5-demethylnobiletin (5-DN), a kind of polymethoxyflavones (PMFs) with high anti-inflammatory activity, was delivered in vitro and in vivo by the nanocarrier of mesoporous silica nanoparticles (MSNs) both in the human keratinocytes HaCaT cell line and the mouse model with psoriasis-like lesions. The drug-loaded nanocarrier system (MSNs@5-DN) significantly improved the biocompatibility and bioavailability of 5-DN. Investigations at cell biological, histopathological, and molecular levels revealed the pharmacological mechanism of the drug delivery system, including the inhibition of inflammatory responses by downregulating the proinflammatory cytokine levels of tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6). The upregulation of anti‑inflammatory cytokine of transforming growth factor-β1 (TGF-β1) and microRNA-17-5p, a critical regulator of the PTEN/AKT pathway, was also observed. The psoriasis-like lesions were markedly ameliorated in the mouse models treated with MSNs@5-DN. The designed drug-loading system shows an enhanced therapeutic outcome for psoriasis-like lesion compared with free 5-DN. This study revealed the synergistic effect of functionalized MSNs loaded with PMFs on the clinical treatment of human psoriasis.

Macrophage metabolism in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) and its inflammatory and often progressive subtype nonalcoholic steatohepatitis (NASH), have emerged as significant contributors to hepatic morbidity worldwide. The pathophysiology of NAFLD/NASH is multifaceted, variable, and remains incompletely understood. The pivotal role of liver-resident and recruited macrophages in the pathogenesis of NAFLD and NASH is widely acknowledged as a crucial factor in innate immunity. The remarkable plasticity of macrophages enables them to assume diverse activation and polarization states, dictated by their immunometabolism microenvironment and functional requirements. Recent studies in the field of immunometabolism have elucidated that alterations in the metabolic profile of macrophages can profoundly influence their activation state and functionality, thereby influencing various pathological processes. This review primarily focuses on elucidating the polarization and activation states of macrophages, highlighting the correlation between their metabolic characteristics and the transition from pro-inflammatory to anti-inflammatory phenotypes. Additionally, we explore the potential of targeting macrophage metabolism as a promising therapeutic approach for the management of NAFLD/NASH.

Explicating genetic architecture governing nutritional quality in pigmented rice

Rice is one of the most important staple plant foods that provide a major source of calories and nutrients for tackling the global hunger index especially in developing countries. In terms of nutritional profile, pigmented rice grains are favoured for their nutritional and health benefits. The pigmented rice varieties are rich sources of flavonoids, anthocyanin and proanthocyanidin that can be readily incorporated into diets to help address various lifestyle diseases. However, the cultivation of pigmented rice is limited due to low productivity and unfavourable cooking qualities. With the advances in genome sequencing, molecular breeding, gene expression analysis and multi-omics approaches, various attempts have been made to explore the genetic architecture of rice grain pigmentation. In this review, we have compiled the current state of knowledge of the genetic architecture and nutritional value of pigmentation in rice based upon the available experimental evidence. Future research areas that can help to deepen our understanding and help in harnessing the economic and health benefits of pigmented rice are also explored.

Phytocompounds and their molecular targets in immunomodulation: a review

Immune cells are important for the healthy function of every organ. The homeostasis of the immune system is selfregulated by T-cells, B-cells, and natural killer cells. The immunomodulation process of immune cells is part of the immunotherapy. According to therapeutic methods of immune responses are categorized as inducing (immunostimulant), amplification (immune booster), attenuation (immunomodulation), and prevention (immunosuppressive) actions. The prevalence of chronic immunological diseases like viral infections, allergies, and cancer is mainly due to the over-activation of the immune system. Further, immunomodulators are reported to manage the severity of chronic immunological disorders. Moreover, these immunomodulator-acting proteins are identified as potential molecular targets for the regulation of the immune system. Moreover, natural compound like phytocompounds are known to bind these targets and modulates the immune system. The specialized phytocompounds like curcumin, quercetin, stilbenes, flavonoids, and lignans are shown the immunomodulatory actions and ameliorate the immunological disorders. The present scenario of a COVID-19 pandemic situation has taught us the need to focus on strengthening the immune system and the development of the most promising immunotherapeutics. This review is focused on an overview of various phytocompounds and their molecular targets for the management of immunological disorders via immunosuppressants and immunostimulants actions.

In Vitro and In Silico Anti-Rheumatic Arthritis Activity of Nyctanthes arbor-tristis

Rheumatoid arthritis (RA) is an autoimmune disease characterized by bone and joint degeneration. Existing anti-inflammatory chemotherapy drugs offer temporary relief but come with undesirable side effects. Herbal medications have shown positive effects on RA symptoms with minimal adverse reactions. In this study, we investigated the potential of Nyctanthes arbor-tristis (NAT) through in vitro and in silico research. Hydroethanolic extracts of harsingar were prepared using the reflux method, containing alkaloids, phenol, saponin, steroids, proteins, tannins, terpenoids, carbohydrates, glycosides, and flavonoids, which exhibited TPC (98.56 ± 0.46 mg GAE/g) and TFC (34.51 ± 0.45 mg CE/g). LC-MS/MS analyzes the active compounds in the extract. NAT exhibited the best scavenging capabilities at 1 mg/mL in anti-oxidant and anti-arthritic activity. Maximum splenocyte proliferation occurred at 250 µg/mL. In vitro cell splenocyte studies revealed the downregulation of TNF-α and the upregulation of IL-10. Additionally, an in silico study demonstrated that bioactive constituents and targets bind with favorable binding affinity. These findings demonstrate the potential of Nyctanthes arbor-tristis in exerting anti-arthritic effects, as supported by in vitro and in silico studies. Further mechanistic research is necessary to validate the therapeutic potential of all phytoconstituents in RA treatment.

Aronia melanocarpa Flavonol Extract-Antiradical and Immunomodulating Activities Analysis

The study of Aronia melanocarpa's (A. melanocarpa) biological activity is focused on obtaining the crude extract and separation of the flavonol compounds. The extraction and fractionation of A. melanocarpa fruits, followed by quantitative analysis, were accomplished using high-performance liquid chromatography and Darco G-60 filtering. This approach enabled the quantification of flavonoids within each fraction. The antioxidative, immunomodulating activities and cytotoxicity with respect to the lymphoblast cell line RPMI-1788 were studied. The flavonol extract of A. melanocarpa has been shown to have a high capacity to neutralize free DPPH and AAPH radicals in vitro. It also caused an accelerated 'respiratory burst' formation of neutrophils and an increase in the metabolic reserves of cells in rats exposed to cyclophosphamide. The reference solution (an equivalent quercetin-rutin blend) contributed to a decrease in lipid peroxidation, intensifying phagocytosis processes. The studied compounds demonstrated their low influence on the leukocyte blood profile in animals.

Pharmacological Activity of Flavonoid Quercetin and Its Therapeutic Potential in Testicular Injury

Quercetin is a natural flavonoid widely found in natural fruits and vegetables. Recent studies have shown that quercetin mediates multiple beneficial effects in a variety of organ damage and diseases, and is considered a healthcare supplement with health-promoting potential. Male infertility is a major health concern, and testicular damage from multiple causes is an important etiology. Previous studies have shown that quercetin has a protective effect on reproductive function. This may be related to the antioxidant, anti-inflammatory, and anti-apoptotic biological activities of quercetin. Therefore, this paper reviews the mechanisms by which quercetin exerts its pharmacological activity and its role in testicular damage induced by various etiologies. In addition, this paper compiles the application of quercetin in clinical trials, demonstrating its practical effects in regulating blood pressure and inhibiting cellular senescence in human patients. However, more in-depth experimental studies and clinical trials are needed to confirm the true value of quercetin for the prevention and protection against testicular injury.

Polymeric Nanoparticles for Delivery of Natural Bioactive Agents: Recent Advances and Challenges

In the last few decades, several natural bioactive agents have been widely utilized in the treatment and prevention of many diseases owing to their unique and versatile therapeutic effects, including antioxidant, anti-inflammatory, anticancer, and neuroprotective action. However, their poor aqueous solubility, poor bioavailability, low GIT stability, extensive metabolism as well as short duration of action are the most shortfalls hampering their biomedical/pharmaceutical applications. Different drug delivery platforms have developed in this regard, and a captivating tool of this has been the fabrication of nanocarriers. In particular, polymeric nanoparticles were reported to offer proficient delivery of various natural bioactive agents with good entrapment potential and stability, an efficiently controlled release, improved bioavailability, and fascinating therapeutic efficacy. In addition, surface decoration and polymer functionalization have opened the door to improving the characteristics of polymeric nanoparticles and alleviating the reported toxicity. Herein, a review of the state of knowledge on polymeric nanoparticles loaded with natural bioactive agents is presented. The review focuses on frequently used polymeric materials and their corresponding methods of fabrication, the needs of such systems for natural bioactive agents, polymeric nanoparticles loaded with natural bioactive agents in the literature, and the potential role of polymer functionalization, hybrid systems, and stimuli-responsive systems in overcoming most of the system drawbacks. This exploration may offer a thorough idea of viewing the polymeric nanoparticles as a potential candidate for the delivery of natural bioactive agents as well as the challenges and the combating tools used to overcome any hurdles.

The research progress on the anxiolytic effect of plant-derived flavonoids by regulating neurotransmitters

Phytopharmaceuticals have attracted a lot of attention due to their multicomponent and multiple targets. The natural phenolic chemicals known as flavonoids are found in a wide variety of plants, fruits, vegetables, and herbs. Recently, they have been found to have modulatory effects on anxiety disorders, with current research focusing on the modulation of neurotransmitters. There has not yet been a review of the various natural flavonoid monomer compounds and total plant flavonoids that have been found to have anxiolytic effects. The study on the anti-anxiety effects of plant-derived flavonoids on neurotransmitters was reviewed in this paper. We, therefore, anticipate that further study on the conformational interaction underlying flavonoids' anti-anxiety effects will offer a theoretical framework for the creation of pertinent treatments.

Murine Fibroblasts and Primary Hepatocytes as Tools When Studying the Efficacy of Potential Therapies for Mucopolysaccharidosis Type I

Mucopolysaccharidosis type I (MPS I) is a metabolic genetic disease caused by the deficiency of a lysosomal enzyme involved in glycosaminoglycans (GAGs) degradation. MPS I cells have a constant level of GAG synthesis, but disturbed degradation means that GAGs accumulate progressively, impairing cell metabolism. GAG metabolism can be modulated by flavonoids, and these are being studied as therapeutics for MPS. We have optimised the protocol for obtaining fibroblasts and hepatocytes from the MPS I murine model and characterised the cells for their suitability as an in vitro model for testing compounds with therapeutic potential. Methods: Murine primary hepatocytes and fibroblasts were used as a cellular model to study the effect of genistein, biochanin A, and kaempferol on the modulation of the GAG synthesis process. Flavonoids were used individually as well as in two-component mixtures. There were no statistically significant differences in GAG synthesis levels from cell types obtained from either wild-type or MPS I mice. We also showed that MPS I fibroblasts and hepatocytes store GAGs, which makes them useful in vitro models for testing the effectiveness of substrate reduction therapies. Furthermore, tested flavonoids had a different impact on GAG synthesis depending on cell type and whether they were used alone or in a mixture. The tested flavonoids reduce GAG synthesis more effectively in fibroblasts than in hepatocytes, regardless of whether they are used individually or in a mixture. Flavonoids modulate the level of GAG synthesis differently depending on cell types, therefore in vitro experiments performed to assess the effectiveness of potential therapies for metabolic diseases should be carried out using more than one cell model, and only such an approach will allow for full answering scientific questions.

Natural Products Against COVID-19 Inflammation: A Mini-Review

Severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) is a virus whose genetic material is positive single-stranded RNA, being responsible for coronavirus disease 2019 (COVID- 19), an infection that compromises the lungs and consequently the respiratory capacity of the infected individual, according to the WHO in November 2021, 249,743,428 cases were confirmed, of which 5,047,652 individuals died due to complications resulting from the infection caused by SARSCOV- 2. As the infection progresses, the individual may experience loss of smell and taste, as well as breathing difficulties, severe respiratory failure, multiple organ failure, and death. Due to this new epidemiological agent in March 2020 it was announced by the director general of the World Health Organization (WHO) a pandemic status, and with that, many research groups are looking for new therapeutic alternatives through synthetic and natural bioactives. This research is a literature review of some in silico studies involving natural products against COVID-19 inflammation published in 2020 and 2021. Work like this presents relevant information to the scientific community, boosting future research and encouraging the use of natural products for the search for new antivirals against COVID-19.

The pharmacological properties and corresponding mechanisms of farrerol: a comprehensive review

CONTEXT

Farrerol, a typical natural flavanone isolated from the traditional Chinese herb 'Man-shan-hong' [Rhododendron dauricum L. (Ericaceae)] with phlegm-reducing and cough-relieving properties, is widely used in China for treating bronchitis and asthma.

OBJECTIVE

To present the anti-inflammatory, antioxidant, vasoactive, antitumor, and antimicrobial effects of farrerol and its underlying molecular mechanisms.

METHODS

The literature was reviewed by searching PubMed, Medline, Web of Knowledge, Scopus, and Google Scholar databases between 2011 and May 2021. The following key words were used: 'farrerol,' 'flavanone,' 'anti-inflammatory,' 'antioxidant,' 'vasoactive,' 'antitumor,' 'antimicrobial,' and 'molecular mechanisms'.

RESULTS

Farrerol showed anti-inflammatory effects mainly mediated via the inhibition of interleukin (IL)-6/8, IL-1β, tumour necrosis factor(TNF)-α, NF-κB, NO, COX-2, JNK1/2, AKT, PI3K, ERK1/2, p38, Keap-1, and TGF-1β. Farrerol exhibited antioxidant effects by decreasing JNK, MDA, ROS, NOX4, Bax/Bcl-2, caspase-3, p-p38 MAPK, and GSK-3β levels and enhancing Nrf2, GSH, SOD, GSH-Px, HO-1, NQO1, and p-ERK levels. The vasoactive effects of farrerol were also shown by the reduced α-SMA, NAD(P)H, p-ERK, p-Akt, mTOR, Jak2, Stat3, Bcl-2, and p38 levels, but increased OPN, occludin, ZO-1, eNOS, CaM, IP3R, and PLC levels. The antitumor effects of farrerol were evident from the reduced Bcl-2, Slug, Zeb-1, and vimentin levels but increased p27, ERK1/2, p38, caspase-9, Bax, and E-cadherin levels. Farrerol reduced α-toxin levels and increased NO production and NF-κB activity to impart antibacterial activity.

CONCLUSIONS

This review article provides a theoretical basis for further studies on farrerol, with a view to develop and utilise farrerol for treating of vascular-related diseases in the future.

Quantification of Paeoniflorin by Fully Validated LC-MS/MS Method: Its Application to Pharmacokinetic Interaction between Paeoniflorin and Verapamil

A rapid, sensitive, and specific LC-MS/MS method was developed and fully validated for the detection of paeoniflorin only in rat plasma, and applied to pharmacokinetic studies, including intravenous, multi-dose oral and combined administrations with verapamil. In this study, tolbutamide was used as the internal standard, and the protein precipitation extraction method, using acetonitrile as the extraction agent, was used for the sample preparation. Subsequently, the supernatant samples were analyzed on a Phenomenex Gemini® NX-C18 column with a flow rate of 1.0 mL/min in a gradient elution procedure. In the extracted rat plasma, the method exhibited high sensitivity (LLOQ of 1.0 ng/mL) upon selecting ammonium adduct ions ([M+NH4]+) as the precursor ions and good linearity over the concentration range of 1.0−2000 ng/mL, with correlation coefficients >0.99. The intra- and inter-batch accuracy RE% values were within ±8.2%, and the precision RSD% values were ≤8.1% and ≤10.0%, respectively. The results show that the method can be successfully applied to quantitate paeoniflorin in biological samples. Additionally, paeoniflorin is subsequently confirmed to be the substrate of the P-gp transporter in vivo and in vitro for the first time, which would be necessary and beneficial to investigate the clinical safety and efficacy of PF with other drugs in the treatment of rheumatoid arthritis.

Effects of Natural Polyphenols on Skin and Hair Health: A Review

The skin is the largest organ of the body and plays multiple essential roles, ranging from regulating temperature, preventing infections, to ultimately affecting human health. A hair follicle is a complex cutaneous appendage. Skin diseases and hair loss have a significant effect on the quality of life and psychosocial adjustment of individuals. However, the available traditional drugs for treating skin and hair diseases may have some insufficiencies; therefore, a growing number of researchers are interested in natural materials that could achieve satisfactory results and minimize adverse effects. Natural polyphenols, named for the multiple phenolic hydroxyl groups in their structures, are promising candidates and continue to be of scientific interest due to their multifunctional biological properties and safety. Polyphenols have a wide range of pharmacological effects. In addition to the most common effect, antioxidation, polyphenols have anti-inflammatory, bacteriostatic, antitumor, and other biological effects associated with reduced risk of a number of chronic diseases. Various polyphenols have also shown efficacy against different types of skin and hair diseases, both in vitro and in vivo, via different mechanisms. Thus, this paper reviews the research progress in natural polyphenols for the protection of skin and hair health, especially focusing on their potential therapeutic mechanisms against skin and hair disorders. A deep understanding of natural polyphenols provides a new perspective for the safe treatment of skin diseases and hair loss.

Antibacterial activity and action mechanism of flavonoids against phytopathogenic bacteria

As the most difficult to control in plant disease, phytopathogenic bacteria cause huge losses to agricultural products and economy worldwide. However, the commercially available bactericides are few and enhance pathogen resistance. To alleviate this situation, 50 flavonoids were evaluated for their antibacterial activities and mechanism of action against two intractable plant bacterial pathogens. The results of bioassays showed that most of the flavonoids exhibited moderate inhibitory effects against Xanthomonas oryzae (Xo) and Xanthomonas axonopodis pv citri (Xac). Remarkably, kaempferol showed excellent antibacterial activity against Xo in vitro (EC₅₀ = 15.91 μg/mL) and quercetin showed the best antibacterial activity against Xac in vitro (EC₅₀ = 14.83 μg/mL), which was better than thiodiazole copper (EC₅₀ values against Xo and Xac were 16.79 μg/mL, 59.13 μg/mL, respectively). Subsequently, in vivo antibacterial activity assay further demonstrated kaempferol exhibited a stronger control effect on bacterial infections than thiodiazole copper. Then, the preliminary antibacterial mechanism of kaempferol was investigated by ultrastructural observations, transcriptomic, qRT-PCR analysis and biochemical index determination. These results showed that kaempferol mainly exerted bacteriostatic effects at the molecular level by affecting bacterial energy metabolism, reducing pathogenicity, and leading to disruption of cellular integrity, leakage of contents and cell death eventually.

Potential common mechanism of four Chinese patent medicines recommended by diagnosis and treatment protocol for COVID-19 in medical observation period

The global epidemic has been controlled to some extent, while sporadic outbreaks still occur in some places. It is essential to summarize the successful experience and promote the development of new drugs. This study aimed to explore the common mechanism of action of the four Chinese patent medicine (CPMs) recommended in the Medical Observation Period COVID-19 Diagnostic and Treatment Protocol and to accelerate the new drug development process. Firstly, the active ingredients and targets of the four CPMs were obtained by the Chinese medicine composition database (TCMSP, TCMID) and related literature, and the common action targets of the four TCMs were sorted out. Secondly, the targets of COVID-19 were obtained through the gene-disease database (GeneCards, NCBI). Then the Venn diagram was used to intersect the common drug targets with the disease targets. And GO and KEGG pathway functional enrichment analysis was performed on the intersected targets with the help of the R package. Finally, the results were further validated by molecular docking and molecular dynamics analysis. As a result, a total of 101 common active ingredients and 21 key active ingredients of four CPMs were obtained, including quercetin, luteolin, acacetin, kaempferol, baicalein, naringenin, artemisinin, aloe-emodin, which might be medicinal substances for the treatment of COVID-19. TNF, IL6, IL1B, CXCL8, CCL2, IL2, IL4, ICAM1, IFNG, and IL10 has been predicted as key targets. 397 GO biological functions and 166 KEGG signaling pathways were obtained. The former was mainly enriched in regulating apoptosis, inflammatory response, and T cell activation. The latter, with 92 entries related to COVID-19, was mainly enriched to signaling pathways such as Coronavirus disease-COVID-19, Cytokine-cytokine receptor interaction, IL-17 signaling pathway, and Toll-like receptor signaling pathway. Molecular docking results showed that 19/21 of key active ingredients exhibited strong binding activity to recognized COVID-19-related targets (3CL of SARS-CoV-2, ACE2, and S protein), even better than one of these four antiviral drugs. Among them, shinflavanone had better affinity to 3CL, ACE2, and S protein of SARS-CoV-2 than these four antiviral drugs. In summary, the four CPMs may play a role in the treatment of COVID-19 by binding flavonoids such as quercetin, luteolin, and acacetin to target proteins such as ACE2, 3CLpro, and S protein and acting on TNF, IL6, IL1B, CXCL8, and other targets to participate in broad-spectrum antiviral, immunomodulatory and inflammatory responses.

Engeletin Alleviates the Inflammation and Apoptosis in Intervertebral Disc Degeneration via Inhibiting the NF-κB and MAPK Pathways

Purpose

Low back pain (LBP) induced by intervertebral disc degeneration (IDD) brings progressively painful status and impairs the normal daily living. Engeletin is a plant-derived medicine with anti-inflammation and antioxidant functions. Therefore, we aim to confirm its protective effects against the intervertebral disc degeneration in vivo and in vitro.

Methods

The cytotoxicity of engeletin was validated by CCK-8 tests. Using the TNF-α to simulate the inflammation status in vitro, the expression of inflammatory mediators and MMP families were determined by qPCR, Western blotting and confocal microscopy. Cell apoptosis was analyzed by flow cytometry and TUNEL assay. The expression of apoptosis-related proteins was tested by Western blotting. The activation of NF-κB and MAPK pathways was evaluated by Western blotting and confocal microscopy. In vivo, percutaneous needle puncture was used to establish the IDD model in rat, and engeletin was administrated via intradiscal injection. The therapeutic effects of engeletin were detected through imaging and histology analysis.

Results

Cell viability tests demonstrated there was little cytotoxicity of engeletin toward NP cells. Pretreatment with engeletin effectively ameliorate the TNF-α-induced up-regulation of inflammatory mediators and MMP families, promoting the anabolism of ECM meanwhile. Cell apoptosis was also attenuated with the addition of engeletin. We found that the activation of MAPK and NF-κB signaling pathways and the nuclear translocation of phosphorylated p65 and p38 were inhibited prominently with the treatment of engeletin which may be the potential molecular mechanism for its anti-inflammation effects. Finally, the IDD induced by percutaneous needle puncture was partially alleviated with the injection of engeletin in vivo.

Conclusion

As a natural compound with little cytotoxicity, engeletin possesses the outstanding anti-inflammation and anti-apoptosis effects in the process of IDD in vitro and in vivo, which may be a promising medicine for the prevention and treatment of IDD-related low back pain.

Scutellaria baicalensis georgi is a promising candidate for the treatment of autoimmune diseases

Autoimmune diseases a group of disorders elicited by unexpected outcome of lymphocytes self-tolerance failure, and the common members of which include multiple sclerosis, systemic lupus erythematosus, inflammatory bowel disease, rheumatoid arthritis, and type 1 diabetes mellitus, etc. The pathogenesis of autoimmune diseases is not fully understood and the current therapeutic regimen’s inefficacy in certain cases coupled with low rates of success, exorbitant financial burden, as well as numerous side effects, which do open new avenues for the role of natural products as novel therapeutic agents for auto-inflammatory disorders. Scutellaria baicalensis Georgi is a well-known and widely-recognized herbal medicine with certain ameliorative effect on diverse inflammation-involved dysfunction. Though recent advances do highlight its potential to be applied in the fight against autoimmune diseases, the specific mechanism and the related opinion on the exploring possibility are still limited which hampered the further progress. Here in this timeline review, we traced and collected the evidence of how Scutellaria baicalensis Georgi and its bioactive contents, namely baicalin, baicalein, wogonoside and wogonin affect autoimmune diseases. Moreover, we also discussed the clinical implications and therapeutic potential of Scutellaria baicalensis Georgi and its bioactive contents in autoimmune diseases treatment.

Flavonoids regulate tumor-associated macrophages - From structure-activity relationship to clinical potential (Review)

In recent years, the strategy for tumor therapy has changed from focusing on the direct killing effect of different types of therapeutic agents on cancer cells to the new mainstream of multi-mode and -pathway combined interventions in the microenvironment of the developing tumor. Flavonoids, with unique tricyclic structures, have diverse and extensive immunomodulatory and anti-cancer activities in the tumor microenvironment (TME). Tumor-associated macrophages (TAMs) are the most abundant immunosuppressive cells in the TME. The regulation of macrophages to fight cancer is a promising immunotherapeutic strategy. This study covers the most comprehensive cognition of flavonoids in regulating TAMs so far. Far more than a simple list of studies, we try to dig out evidence of crosstalk at the molecular level between flavonoids and TAMs from literature, in order to discuss the most relevant chemical structure and its possible relationship with the multimodal pharmacological activity, as well as systematically build a structure-activity relationship between flavonoids and TAMs. Additionally, we point out the advantages of the macro-control of flavonoids in the TME and discuss the potential clinical implications as well as areas for future research of flavonoids in regulating TAMs. These results will provide hopeful directions for the research of antitumor drugs, while providing new ideas for the pharmaceutical industry to develop more effective forms of flavonoids.

The effect of immunomodulatory properties of naringenin on the inhibition of inflammation and oxidative stress in autoimmune disease models: a systematic review and meta-analysis of preclinical evidence

BACKGROUND/OBJECTIVE

Naringenin is a member of the flavonoid family that can perform many biological processes to treat a wide range of inflammatory diseases and pathological conditions related to oxidative stress (OS). Naringenin immunomodulatory activities have been the subject of recent research as an effective alternative treatment for autoimmune disorders. The effects of naringenin on the levels of inflammatory biomarkers and OS factors in animal models of autoimmune disorders (ADs) were studied in this meta-analysis.

METHODS

Up until January 2022, electronic databases such as Cochrane Library and EMBASE, PubMed, Web of Science, and Scopus were used to conduct a comprehensive literature search in English language. To evaluate the effect of naringenin on inflammatory mediators, such as TNF-α, IL-6, IL-β, IFN-γ, NF-κB, and nitric oxide, and OS biomarkers, such as CAT, SOD, GPx, GSH and MDA, in AD models, we measured the quality assessment and heterogeneity test using the PRISMA checklist protocol and I² statistic, respectively. A random-effects model was employed based on the heterogeneity test, and then pooled data were standardized as mean difference (SMD) with a 95% confident interval (CI).

RESULTS

We excluded all clinical trials, cell experiment studies, animal studies with different parameters, non-autoimmune disease models, and an inadequate series of studies for quantitative synthesis. Finally, from 627 potentially reports, 12 eligible studies were included in the meta-analysis. Data were collected from several groups. Of these, 153 were in the naringenin group and 149 were in the control group. Our meta-analysis of the pooled data for the parameters of inflammation and OS indicated that naringenin significantly reduced the levels of NF-κB (SMD - 3.77, 95% CI [- 6.03 to - 1.51]; I² = 80.1%, p = 0.002), IFN-γ (SMD - 6.18, 95% CI [- 8.73 to - 3.62]; I² = 53.7%, p = 0.115), and NO (SMD - 3.97, 95% CI [- 5.50 to - 2.45]; I² = 73.4%, p = 0.005), IL-1β (SMD - 4.23, 95% CI [- 5.09 to - 3.37]; I² = 0.0%, p = 0.462), IL-6 (SMD - 5.84, 95% CI [- 7.83 to - 3.85]; I² = 86.5%, p < 0.001), and TNF-α (SMD - 5.10, 95% CI [- 6.34 to - 3.86]; I² = 74.7%, p < 0.001). These findings also demonstrated the efficacy of naringenin on increasing the levels of CAT (SMD 4.19, 95% CI [1.33 to 7.06]; I² = 79.9%, p = 0.007), GSH (SMD 4.58, 95% CI [1.64 to 7.51]; I² = 90.5%, p < 0.001), and GPx (SMD 9.65, 95% CI [2.56 to 16.74]; I² = 86.6%, p = 0.001) and decreasing the levels of MDA (SMD - 3.65, 95% CI [- 4.80 to - 2.51]; I² = 69.4%, p = 0.001) than control groups. However, treatment with naringenin showed no statistically difference in SOD activity (SMD 1.89, 95% CI [- 1.11 to 4.89]; I² = 93.6%, p < 0.001).

CONCLUSION

Overall, our findings revealed the immunomodulatory potential of naringenin as an alternative treatment on inhibition of inflammation and OS in several autoimmune-related diseases. Nevertheless, regarding the limitation of clinical trials, strong preclinical models and clinical settings in the future are needed that address the effects of naringenin on ADs. Before large-scale clinical studies, precise human pharmacokinetic investigations are required to determine the dosage ranges and evaluate the initial safety profile of naringenin.

Registered human trials addressing environmental and occupational toxicant exposures: Scoping review of immunological markers and protective strategies

Exposure to pollution is a worldwide societal challenge participating in the etiology and progression of different diseases. However, the scarce information hinders our understanding of the actual level of human exposure and its specific effects. Inadequate and excessive immune responses underlie diverse chronic diseases. Yet, it is unclear which and how toxicant exposures affect the immune system functions. There is a multiplicity of immunological outcomes and biomarkers being studied in human trials related to exposure to different toxicants but still without clear evidence of their value as biomarkers of exposure or effect. The main aim of this study was to collect scientific evidence and identify relevant immunological biomarkers used at the clinical level for toxicant exposures. We used the platform clinical trials.gov as a database tool. First, we performed a search combining research items related to toxicants and immunological parameters. The resulting117 clinical trials were examined for immune-related outcomes and specific biomarkers evaluated in subjects exposed to occupational and environmental toxicants. After categorization, relevant immunological outcomes and biomarkers were identified related to systemic and airway inflammation, modulation of immune cells, allergy and autoimmunity. In general, the immune markers related to inflammation are more frequently investigated for exposure to pollutants, namely IL-6, C-reactive protein (CRP) and nitric oxide (NO). Nevertheless, the data also indicated that prospective biomarkers of effect are gaining ground and a guiding representation of the established and novel biomarkers is suggested for upcoming trials. Finally, potential protective strategies to mitigate the adverse effects of specific toxicants are underlined for future studies.

Enhanced Anti-Inflammatory Effects of Silibinin and Capsaicin Combination in Lipopolysaccharide-Induced RAW264.7 Cells by Inhibiting NF-κB and MAPK Activation

Silibinin and capsaicin both are natural product molecules with diverse biological activities. In this article, we investigated the anti-inflammatory effects of silibinin combined with capsaicin in lipopolysaccharide (LPS)-induced RAW264.7 cells. The results showed that silibinin combined with capsaicin strongly inhibited LPS-induced nitric oxide (NO), tumor necrosis factor-α (TNF-α), Interleukin-6 (IL-6), and COX-2. Moreover, silibinin combined with capsaicin potently inhibited nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. The results of the present study indicate that silibinin combined with capsaicin effectively inhibits inflammation.

Non-Volatile and Volatile Bioactives of Salvia officinalis L., Thymus serpyllum L. and Laurus nobilis L. Extracts with Potential Use in the Development of Functional Beverages

Functional beverages based on herbal extracts are highly demanded products due to the presence of bioactives with promising health benefits and interesting and characteristic sensory properties. Mediterranean medicinal and aromatic herbs contain a wide range of bioactives (non-volatile polyphenols, volatile terpenes) that are important constituents of herbal extracts and essential oils. The antioxidant capacity and potential health benefits of these bioactives could be associated with their synergistic effects. Therefore, this study aimed to characterize the non-volatile and volatile bioactives of sage (Salvia officinalis L.), wild thyme (Thymus serpyllum L.) and laurel (Laurus nobilis L.) aqueous extracts and their two- and three-component mixtures as well as their antioxidant capacity. The content of total phenols, flavonoids, hydroxycinnamic acids and flavonols was determined spectrophotometrically. Individual polyphenols were analyzed by LC-MS/MS, the volatiles were analyzed by HS-SPME/GC-MS, and the antioxidant capacity was analyzed by ORAC and DPPH assays. The results showed that aqueous extracts of all examined herbs and their mixtures contained a high content of phenolic compounds ranging from 0.97 to 2.79 g L^-1 of the sample, among which the most common were flavonols. At the same time, mono- and sesquiterpenes were the main volatiles. All extracts showed high antioxidant capacity, especially L. nobilis (781.62 ± 5.19 μmol TE mL^-1 of the sample in the DPPH assay; 1896.10 ± 8.77 μmol TE mL^-1 of the sample in the ORAC assay) and the two-component mixture of L. nobilis and T. serpyllum (679.12 ± 5.19 μmol TE mL^-1 in the DPPH assay; 1913.38 ± 8.77 μmol TE mL^-1 in the ORAC assay). Mixtures of herbal extracts have been shown to possess additive or synergistic effects, consequently contributing to higher antioxidant capacity. Therefore, two-component mixtures of herbal extracts showed promising potential for the production of functional beverages.

Bioactive Compounds and Their Derivatives: An Insight into Prospective Phytotherapeutic Approach against Alzheimer’s Disease

Alzheimer's disease (AD) is a common neurodegenerative brain disorder that causes cellular response alterations, such as impaired cholinergic mechanism, amyloid-beta (Aβ) AD aggregation, neuroinflammation, and several other pathways. AD is still the most prevalent form of dementia and affects many individuals across the globe. The exact cause of the disorder is obscure. There are yet no effective medications for halting, preventing, or curing AD's progress. Plenty of natural products are isolated from several sources and analyzed in preclinical and clinical settings for neuroprotective effects in preventing and treating AD. In addition, natural products and their derivatives have been promising in treating and preventing AD. Natural bioactive compounds play an active modulatory role in the pathological molecular mechanisms of AD development. This review focuses on natural products from plant sources and their derivatives that have demonstrated neuroprotective activities and maybe promising to treat and prevent AD. In addition, this article summarizes the literature pertaining to natural products as agents in the treatment of AD. Rapid metabolism, nonspecific targeting, low solubility, lack of BBB permeability, and limited bioavailability are shortcomings of most bioactive molecules in treating AD. We can use nanotechnology and nanocarriers based on different types of approaches.

Flavonoids Target Human Herpesviruses That Infect the Nervous System: Mechanisms of Action and Therapeutic Insights

Human herpesviruses (HHVs) are large DNA viruses with highly infectious characteristics. HHVs can induce lytic and latent infections in their host, and most of these viruses are neurotropic, with the capacity to generate severe and chronic neurological diseases of the peripheral nervous system (PNS) and central nervous system (CNS). Treatment of HHV infections based on strategies that include natural products-derived drugs is one of the most rapidly developing fields of modern medicine. Therefore, in this paper, we lend insights into the recent advances that have been achieved during the past five years in utilizing flavonoids as promising natural drugs for the treatment of HHVs infections of the nervous system such as alpha-herpesviruses (herpes simplex virus type 1, type 2, and varicella-zoster virus), beta-herpesviruses (human cytomegalovirus), and gamma-herpesviruses (Epstein–Barr virus and Kaposi sarcoma-associated herpesvirus). The neurological complications associated with infections induced by the reviewed herpesviruses are emphasized. Additionally, this work covers all possible mechanisms and pathways by which flavonoids induce promising therapeutic actions against the above-mentioned herpesviruses.

Alpinetin: A Review of Its Pharmacology and Pharmacokinetics

Flavonoids isolated from medicinal herbs have been utilized as valuable health-care agents due to their virous biological applications. Alpinetin is a natural flavonoid that emerges in many widely used medicinal plants, and has been frequently applied in Chinese patent drugs. Accumulated evidence has demonstrated that alpinetin possesses a broad range of pharmacological activities such as antitumor, antiinflammation, hepatoprotective, cardiovascular protective, lung protective, antibacterial, antiviral, neuroprotective, and other properties through regulating multiple signaling pathways with low systemic toxicity. However, pharmacokinetic studies have documented that alpinetin may have poor oral bioavailability correlated to its extensive glucuronidation. Currently, the reported pharmacological properties and pharmacokinetics profiles of alpinetin are rare to be scientifically reviewed. In this article, we aimed to highlight the mechanisms of action of alpinetin in various diseases to strongly support its curative potentials for prospective clinical applications. We also summarized the pharmacokinetics properties and proposed some viable strategies to convey an appreciable reference for future advances of alpinetin in drug development.

Cellular and Gene Expression Response to the Combination of Genistein and Kaempferol in the Treatment of Mucopolysaccharidosis Type I

Flavonoids are investigated as therapeutics for mucopolysaccharidosis, a metabolic disorder with impaired glycosaminoglycan degradation. Here we determined the effects of genistein and kaempferol, used alone or in combination, on cellular response and gene expression in a mucopolysaccharidosis type I model. We assessed the cell cycle, viability, proliferation, subcellular localization of the translocation factor EB (TFEB), number and distribution of lysosomes, and glycosaminoglycan synthesis after exposure to flavonoids. Global gene expression was analysed using DNA microarray and quantitative PCR. The type and degree of flavonoid interaction were determined based on the combination and dose reduction indexes. The combination of both flavonoids synergistically inhibits glycosaminoglycan synthesis, modulates TFEB localization, lysosomal number, and distribution. Genistein and kaempferol in a 1:1 ratio regulate the expression of 52% of glycosaminoglycan metabolism genes. Flavonoids show synergy, additivity, or slight antagonism in all analysed parameters, and the type of interaction depends on the concentration and component ratios. With the simultaneous use of genistein and kaempferol in a ratio of 4:1, even a 10-fold reduction in the concentration of kaempferol is possible. Flavonoid mixtures, used as the treatment of mucopolysaccharidosis, are effective in reducing glycosaminoglycan production and storage and show a slight cytotoxic effect compared to single-flavonoid usage.

Glytabastan B, a coumestan isolated from Glycine tabacina, alleviated synovial inflammation, osteoclastogenesis and collagen-induced arthritis through inhibiting MAPK and PI3K/AKT pathways

The roots of Glycine tabacina are used to treat rheumatoid arthritis (RA) and joint infection in folk medicine. Glytabastan B (GlyB), a newly reported coumestan isolated from this species, was found to significantly attenuate IL-1β-induced inflammation in SW982 human synovial cells at 3 and 6 μM, as evidenced by the decreased levels of pro-inflammatory mediators and matrix metalloproteinases (MMPs). GlyB also suppressed RANKL-induced osteoclastogenesis, decreased the expression of osteoclastogenic markers (NFATc1, CTSK, MMP-9) and osteoclast-mediated bone resorption. Further, GlyB administration (12.5 and 25 mg/kg) significantly inhibited inflammation, osteoclast formation and disease progression in collagen-induced arthritis (CIA) mice. Integration of network pharmacology, quantitative phosphoproteomic and experimental pharmacology results revealed that these beneficial actions were closely associated with the blockade of GlyB on the activation of MAPK, PI3K/AKT and their downstream signals including NF-κB and GSK3β/NFATc1. Drug affinity responsive target stability (DARTS) assay, cellular thermal shift (CETSA) assay and molecular docking analysis confirmed that there were direct interactions between GlyB and its target proteins ERK2, JNK1 and class Ⅰ PI3K catalytic subunit p110 (α, β, δ and γ), which significantly contributed to the inhibition of activation of MAPK and PI3K/AKT pathways. In conclusion, these results strongly suggest GlyB is a promising multiple-target candidate for the development of agents for the prevention and treatment of RA.

Assessment role of total phenols and flavonoids extracted from Pleurotus columbinus mushroom on the premature ovarian failure induced by chemotherapy in rats

BACKGROUND

Many species of mushroom contain an assortment of free radical scavengers (Phenolics and Flavonoids compounds) that have made them nutritionally beneficial and a source of expansion of drug production. In this study, we examined the preventive and remedial role of total phenol extract from Pleurotus columbines (TP) in alleviating the consequences of cyclophosphamide (CTX) on the ovaries of female rats. Rats were randomly assigned to four groups: healthy controls, cyclophosphamide (CTX), received a TP (100 mg/kg) orally daily for 14 days and curative group: CTX-TP, we determined and identified a total phenol from a mushroom extract and examined it as an antioxidant agent. To investigate the therapeutic influence, it was administrated 2 weeks after CTX. To assess the impact of TP on ovarian damage caused by CTX, ovarian hormone tests were performed such as luteinizing hormone (LH), 17-β-estradiol (E2), and anti-mullerian hormone (AMH). Besides, follicle-stimulating hormone (FSH) in serum was evaluated, and histopathological analysis of the ovary was examined.

RESULTS

This study indicates that treatment with TP decreased the severity of cyclophosphamide-induced ovary injury by reducing inflammation and apoptotic effects and increasing the activity of antioxidants.

CONCLUSIONS

TP could be used to alleviate cyclophosphamide-induced ovary injury.

Treatment of Lupus Nephritis from Iranian Traditional Medicine and Modern Medicine Points of View: A Comparative Study

Objective

Nephritis or kidney inflammation is characterized as one of the most common renal disorders leading to serious damage to the kidneys. Nephritis, especially lupus nephritis (LN), has remained as the main cause of chronic renal failure which needs serious therapeutic approaches such as dialysis and kidney transplant. Heredity, infection, high blood pressure, inflammatory diseases such as lupus erythematosus and inflammatory bowel disease, and drug-related side effects are known as the main causes of the disease. According to Iranian traditional medicine (ITM), infectious diseases and fever are the main reasons of nephritis, which is called “Varam-e-Kolye” (VK).

Results

There are various plant-based remedies recommended by ITM for the treatment of nephritis, as discussed herein, comparing with those available in the modern medicine. There is no definite cure for the treatment of nephritis, and immunosuppressive drugs such as corticosteroids and nonsteroidal anti-inflammatory drugs, antibiotics, diuretics, analgesics, and finally dialysis and kidney transplantation are usually used. Based on the efficacy of medicinal plants, jujube (Ziziphus jujuba), almond (Prunus amygdalus), pumpkin seeds (Cucurbita pepo), purslane (Portulaca oleracea), and fig (Ficus carica) were found to be effective for the treatment of kidney inflammation in ITM.

Conclusion

Considering the fact that there is no efficient strategy for the treatment of nephritis, use of herbal medicine, particularly based on the fruits or nuts that have been safely used for several years can be considered as a versatile supplement along with other therapeutic methods.

Therapeutic potential of triptolide in autoimmune diseases and strategies to reduce its toxicity

With the increasing epidemiology of autoimmune disease worldwide, there is an urgent need for effective drugs with low cost in clinical treatment. Triptolide, the most potent bioactive compound from traditional Chinese herb Tripterygium Wilfordii Hook F, possesses immunosuppression and anti-inflammatory activity. It is a potential drug for the treatment of various autoimmune diseases, but its clinical application is still restricted due to severe toxicity. In this review, the pharmacodynamic effects and pharmacological mechanisms of triptolide in autoimmune diseases are summarized. Triptolide exerts therapeutic effect by regulating the function of immune cells and the expression of cytokines through inflammatory signaling pathways, as well as maintaining redox balance and gut microbiota homeostasis. Meanwhile, the research progress on toxicity of triptolide to liver, kidney, reproductive system, heart, spleen, lung and gastrointestinal tract has been systematically reviewed. In vivo experiments on different animals and clinical trials demonstrate the dose- and time- dependent toxicity of triptolide through different administration routes. Furthermore, we focus on the strategies to reduce toxicity of triptolide, including chemical structural modification, novel drug delivery systems, and combination pharmacotherapy. This review aims to reveal the potential therapeutic prospect and limitations of triptolide in treating autoimmune diseases, thus providing guiding suggestions for further study and promoting its clinical translation.