Bioassay-guided isolation and mechanistic action of anti-inflammatory agents from Clerodendrum inerme leaves

The bioflavonoid hispidulin effectively attenuates T helper type 2-driven allergic lung inflammation in the ovalbumin-induced allergic asthma mouse model

BACKGROUND

Allergic asthma affects nearly 300 million people worldwide and causes ahigh burden of disability and death. Effective treatments rely heavily on corticosteroids, which are associated with various complications. So, the alternative treatment is of significance. Hispidulin is a bioflavonoid found in herbs that were used in traditional medicine to treat inflammatory diseases, including asthma. This study aims to investigate the efficacy of hispidulin compound in the treatment of allergic lung inflammation using the mouse model of allergic asthma.

METHODS

BALB/c mice were sensitized and challenged with chicken egg ovalbumin. Cells and cytokines from bronchoalveolar lavage (BAL) fluid were examined. Lung tissues were collected for histologic study. Mouse splenic CD4+ cells were cultured to observe the effect of hispidulin on T-helper 2 (Th2) cell differentiation in vitro.

RESULTS

Hispidulin treatment could alleviate allergic airway inflammation as evidenced by a significant reduction in the inflammatory cell count and Th2 cytokines interleukin (IL)-4, IL-5, IL-13 in BAL fluid. Histologic examination of lung tissues revealed lower inflammatory cell infiltration to the bronchi and less airway goblet cell hyperplasia in the treatment group compared to the control group. At the cellular level, hispidulin (25, 50, and 100 μM) was found to directly suppress the differentiation and proliferation of Th2 cells and to suppress the production of Th2 cytokines, such as IL-4, IL-5, and IL-13, in vitro.

CONCLUSIONS

Hispidulin treatment was shown to effectively decrease type 2 lung inflammation in an ovalbumin-induced allergic asthma mouse model by directly suppressing Th2 cell differentiation and functions.

Pharmaceutical Potential of Remedial Plants and Helminths for Treating Inflammatory Bowel Disease

Research is increasingly revealing that inflammation significantly contributes to various diseases, particularly inflammatory bowel disease (IBD). IBD is a major medical challenge due to its chronic nature, affecting at least one in a thousand individuals in many Western countries, with rising incidence in developing nations. Historically, indigenous people have used natural products to treat ailments, including IBD. Ethnobotanically guided studies have shown that plant-derived extracts and compounds effectively modulate immune responses and reduce inflammation. Similarly, helminths and their products offer unique mechanisms to modulate host immunity and alleviate inflammatory responses. This review explored the pharmaceutical potential of Aboriginal remedial plants and helminths for treating IBD, emphasizing recent advances in discovering anti-inflammatory small-molecule drug leads. The literature from Scopus, MEDLINE Ovid, PubMed, Google Scholar, and Web of Science was retrieved using keywords such as natural product, small molecule, cytokines, remedial plants, and helminths. This review identified 55 important Aboriginal medicinal plants and 9 helminth species that have been studied for their anti-inflammatory properties using animal models and in vitro cell assays. For example, curcumin, berberine, and triptolide, which have been isolated from plants; and the excretory-secretory products and their protein, which have been collected from helminths, have demonstrated anti-inflammatory activity with lower toxicity and fewer side effects. High-throughput screening, molecular docking, artificial intelligence, and machine learning have been engaged in compound identification, while clustered regularly interspaced short palindromic repeats (CRISPR) gene editing and RNA sequencing have been employed to understand molecular interactions and regulations. While there is potential for pharmaceutical application of Aboriginal medicinal plants and gastrointestinal parasites in treating IBD, there is an urgent need to qualify these plant and helminth therapies through reproducible clinical and mechanistic studies.

Screening of phytochemicals from Clerodendrum inerme (L.) Gaertn as potential anti-breast cancer compounds targeting EGFR: an in-silico approach

Breast cancer (BC) is the most prevalent malignancy among women around the world. The epidermal growth factor receptor (EGFR) is a tyrosine kinase receptor (RTK) of the ErbB/HER family. It is essential for triggering the cellular signaling cascades that control cell growth and survival. However, perturbations in EGFR signaling lead to cancer development and progression. Hence, EGFR is regarded as a prominent therapeutic target for breast cancer. Therefore, in the current investigation, EGFR was targeted with phytochemicals from Clerodendrum inerme (L.) Gaertn (C. inerme). A total of 121 phytochemicals identified by gas chromatography-mass spectrometry (GC-MS) analysis were screened against EGFR through molecular docking, ADMET analyses (Absorption, Distribution, Metabolism, Excretion, and Toxicity), PASS predictions, and molecular dynamics simulation, which revealed three potential hit compounds with CIDs 10586 [i.e. alpha-bisabolol (-6.4 kcal/mol)], 550281 [i.e. 2,(4,4-Trimethyl-3-hydroxymethyl-5a-(3-methyl-but-2-enyl)-cyclohexene) (-6.5 kcal/mol)], and 161271 [i.e. salvigenin (-7.4 kcal/mol)]. The FDA-approved drug gefitinib was used to compare the inhibitory effects of the phytochemicals. The top selected compounds exhibited good ADMET properties and obeyed Lipinski's rule of five (ROF). The molecular docking analysis showed that salvigenin was the best among the three compounds and formed bonds with the key residue Met 793. Furthermore, the molecular mechanics generalized born surface area (MMGBSA) calculations, molecular dynamics simulation, and normal mode analysis validated the binding affinity of the compounds and also revealed the strong stability and compactness of phytochemicals at the docked site. Additionally, DFT and DOS analyses were done to study the reactivity of the compounds and to further validate the selected phytochemicals. These results suggest that the identified phytochemicals possess high inhibitory potential against the target EGFR and can treat breast cancer. However, further in vitro and in vivo investigations are warranted towards the development of these constituents into novel anti-cancer drugs.Communicated by Ramaswamy H. Sarma.

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.

Indigenous Uses, Phytochemical Analysis, and Anti-Inflammatory Properties of Australian Tropical Medicinal Plants

Australian tropical plants have been a rich source of food (bush food) and medicine to the first Australians (Aboriginal people), who are believed to have lived for more than 50,000 years. Plants such as spreading sneezeweed (Centipeda minima), goat’s foot (Ipomoea pes-caprae), and hop bush (Dodonaea viscosa and D. polyandra) are a few popular Aboriginal medicinal plants. Thus far, more than 900 medicinal plants have been recorded in the tropical region alone, and many of them are associated with diverse ethnomedicinal uses that belong to the traditional owners of Aboriginal people. In our effort to find anti-inflammatory lead compounds in collaboration with Aboriginal communities from their medicinal plants, we reviewed 78 medicinal plants used against various inflammation and inflammatory-related conditions by Aboriginal people. Out of those 78 species, we have included only 45 species whose crude extracts or isolated pure compounds showed anti-inflammatory properties. Upon investigating compounds isolated from 40 species (for five species, only crude extracts were studied), 83 compounds were associated with various anti-inflammatory properties. Alphitolic acid, Betulinic acid, Malabaric acid, and Hispidulin reduced proinflammatory cytokines and cyclooxygenase enzymes (COX-1 and 2) with IC₅₀ values ranging from 11.5 to 46.9 uM. Other promising anti-inflammatory compounds are Brevilin A (from Centipeda minima), Eupalestin, and 5′-methoxy nobiletin (from Ageratum conyzoides), Calophyllolide (from Calophyllum inophyllum), and Brusatol (from Brucea javanica). D. polyandra is one example of an Aboriginal medicinal plant from which a novel anti-inflammatory benzoyl ester clerodane diterpenoid compound was obtained (compound name not disclosed), and it is in the development of topical medicines for inflammatory skin diseases. Medicinal plants in the tropics and those associated with indigenous knowledge of Aboriginal people could be a potential alternative source of novel anti-inflammatory therapeutics.

Synergistic immunosuppressive effect of hispidulin and nepetin mixtures on human T lymphocytes

BACKGROUND

Clerodendrum petasites S. Moore predominantly contains hispidulin (His) and nepetin (Nep) which are immunosuppressive potentials. Although the effect of individual compounds was previously confirmed, a cumulative suppression of these flavonoid mixtures is unknown. This study thus investigated their inhibitory effects and cytotoxicity on T cells by using His:Nep ratios following a naturally-occurring dose (3:1) and optimized doses (1:1 and 1:3).

MATERIALS AND METHODS

Anti-CD3/28 stimulated peripheral blood mononuclear cells were treated with individual compounds and their mixtures. Changes in early cell activation markers in activated T cells and apoptosis were analyzed by a flow cytometer.

RESULTS

Mixtures at 3:1 suppressed CD69 and CD25 expression in CD4⁺ and CD8⁺ T cells in a dose-dependent manner. At the highest concentration of 200 µM His +66.7 µM Nep, over 90% inhibition was observed for CD25 expression in CD4⁺ and CD8⁺ T cells, whereas a lesser effect was observed for CD69 expression. A dose-dependent inhibition was still observed when using 1:1 and 1:3 ratios. Interestingly, 80-97% inhibition were observed in CD69 and CD25 expression without inducing cell death after treated with the highest doses of each ratio (66.7 µM His +200 µM Nep and 200 µM His +200 µM Nep). These mixtures were also exhibited a better suppression than individual compounds.

CONCLUSIONS

The optimized mixture of His and Nep at 66.7:200 µM is suggested for further study due to a greater suppressive effect than a single compound or a naturally-occurring dose.

Pulmonary arterial hypertension and flavonoids: A role in treatment

Pulmonary arterial hypertension (PAH) is a high mortality progressive pulmonary vascular disease that can lead to right heart failure. The use of clinical drugs for the treatment of PAH is limited to a great extent because of its single target and high price. Flavonoids are widely distributed in nature, and have been found in fruits, vegetables, and traditional Chinese medicine. They have diverse biological activities and various pharmacological effects such as antitumor, antioxidation, and anti-inflammatory. This review summarizes the progress in pharmacodynamics and mechanism of flavonoids in the treatment of PAH in recent years, in order to provide some theoretical references for relevant researchers.

The Effect of Hispidulin, a Flavonoid from Salvia plebeia, on Human Nasopharyngeal Carcinoma CNE-2Z Cell Proliferation, Migration, Invasion, and Apoptosis

Nasopharyngeal carcinoma (NPC) is a common malignant head and neck tumor. Drug resistance and distant metastasis are the predominant cause of treatment failure in NPC patients. Hispidulin is a flavonoid extracted from the bioassay-guided separation of the EtOH extract of Salvia plebeia with strong anti-proliferative activity in nasopharyngeal carcinoma cells (CNE-2Z). In this study, the effects of hispidulin on proliferation, invasion, migration, and apoptosis were investigated in CNE-2Z cells. The [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) assay and the colony formation assay revealed that hispidulin could inhibit CNE-2Z cell proliferation. Hispidulin (25, 50, 100 μM) also induced apoptosis in a dose-dependent manner in CNE-2Z cells. The expression of Akt was reduced, and the expression of the ratio of Bax/Bcl-2 was increased. In addition, scratch wound and transwell assays proved that hispidulin (6.25, 12.5, 25 μM) could inhibited the migration and invasion in CNE-2Z cells. The expressions of HIF-1α, MMP-9, and MMP-2 were decreased, while the MMPs inhibitor TIMP1 was enhanced by hispidulin. Moreover, hispidulin exhibited potent suppression tumor growth and low toxicity in CNE-2Z cancer-bearing mice at a dosage of 20 mg/kg/day. Thus, hispidulin appears to be a potentially effective agent for NPC treatment.

Acacetin suppresses the electrocardiographic and arrhythmic manifestations of the J wave syndromes

Background

J wave syndromes (JWS), including Brugada (BrS) and early repolarization syndromes (ERS), are associated with increased risk for life-threatening ventricular arrhythmias. Pharmacologic approaches to therapy are currently very limited. Here, we evaluate the effects of the natural flavone acacetin.

Methods

The effects of acacetin on action potential (AP) morphology and transient outward current (I_to) were first studied in isolated canine RV epicardial myocytes using whole-cell patch clamp techniques. Acacetin’s effects on transmembrane APs, unipolar electrograms and transmural ECGs were then studied in isolated coronary-perfused canine RV and LV wedge preparations as well as in whole-heart, Langendorff-perfused preparations from which we recorded a 12 lead ECG and unipolar electrograms. Using floating glass microelectrodes we also recorded transmembrane APs from the RVOT of the whole-heart model. The I_to agonist NS5806, sodium channel blocker ajmaline, calcium channel blocker verapamil or hypothermia (32°C) were used to pharmacologically mimic the genetic defects and conditions associated with JWS, thus eliciting prominent J waves and provoking VT/VF.

Results

Acacetin (5–10 μM) reduced I_to density, AP notch and J wave area and totally suppressed the electrocardiographic and arrhythmic manifestation of both BrS and ERS, regardless of the experimental model used. In wedge and whole-heart models of JWS, increasing I_to with NS5806, decreasing I_Na or I_Ca (with ajmaline or verapamil) or hypothermia all resulted in accentuation of epicardial AP notch and ECG J waves, resulting in characteristic BrS and ERS phenotypes. Phase 2-reentrant extrasystoles originating from the RVOT triggered VT/VF. The J waves in leads V1 and V2 were never associated with a delay of RVOT activation and always coincided with the appearance of the AP notch recorded from RVOT epicardium. All repolarization defects giving rise to VT/VF in the BrS and ERS models were reversed by acacetin, resulting in total suppression of VT/VF.

Conclusions

We present experimental models of BrS and ERS capable of recapitulating all of the ECG and arrhythmic manifestations of the JWS. Our findings provide definitive support for the repolarization but not the depolarization hypothesis proposed to underlie BrS and point to acacetin as a promising new pharmacologic treatment for JWS.

Hispidulin: A novel natural compound with therapeutic potential against human cancers

Cancer is one of the most devastating disease and leading cause of death worldwide. The conventional anticancer drugs are monotarget, toxic, expensive and suffer from drug resistance. Development of multi-targeted drugs from natural products has emerged as a new paradigm to overcome aforementioned conventionally encountered obstacles. Hispidulin (HIS), is a biologically active natural flavone with versatile biological and pharmacological activities. The anticancer, antimutagenic, antioxidative and anti-inflammatory properties of HIS have been reported. The aim of this review is to summarize the findings of several studies over the last few decades on the anticancer activity of HIS published in various databases including PubMed, Google Scholar, and Scopus. HIS has been shown to reduce the growth of cancer cells by inducing apoptosis, arresting cell cycle, inhibiting angiogenesis, invasion and metastasis via modulating multiple signaling pathways implicated in cancer initiation and progression. Multitargeted anticancer activity of HIS remains the strongest point for developing it into potential anticancer drug. We also highlighted the natural sources, anticancer mechanism, cellular targets, and chemo-sensitizing potential of HIS. This review will provide bases for design and conduct of further pre-clinical and clinical trials to develop HIS into a lead structure for future anticancer therapy.

Acacetin, a flavone with diverse therapeutic potential in cancer, inflammation, infections and other metabolic disorders

BACKGROUND

Acacetin is a di-hydroxy and mono-methoxy flavone present in various plants, including black locust, Damiana, Silver birch. Literature information revealed that acacetin exhibits an array of pharmacological potential including chemopreventive and cytotoxic properties in cancer cell lines, prevents ischemia/reperfusion/myocardial infarction-induced cardiac injury, lipopolysaccharide (LPS), 1-methyl-4-phenyl pyridinium ion (MPP+) and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP)-induced neuroinflammation, LPS and sepsis-induced lung injury, rheumatoid and collagen-induced arthritis, inhibit the microbial growth, obesity, viral-mediated infections as well as hepatic protection.

PURPOSE

This review highlights the therapeutic potential of acacetin, with updated and comprehensive information on the biological sources, chemistry, and pharmacological properties along with the possible mechanism of action, safety aspects, and future research opportunities.

STUDY DESIGN

The information was retrieved from various search engines, including Pubmed, SciFinder, Science direct, Inxight:drugs, Google scholar, and Meta cyc.

RESULT

The first section of this review focuses on the detailed biological source of acacetin, chromatographic techniques used for isolation, chemical characteristics, the method for the synthesis of acacetin, and the available natural and synthetic derivatives. Subsequently, the pharmacological activities, including anti-cancer, anti-inflammatory, anti-viral, anti-microbial, anti-obesity, have been discussed. The pharmacokinetics data and toxicity profile of acacetin are also discussed.

CONCLUSION

Acacetin is a potent molecule reported for its strong anti-inflammatory and anti-cancer activity, however further scientific evidence is essential to validate its potency in disease models associated with inflammation and cancer. There is limited information available for toxicity profiling of acacetin; therefore, further studies would aid in establishing this natural flavone as a potent candidate for research studies at clinical setup.

Enhanced production and immunomodulatory activity of levan from the acetic acid bacterium, Tanticharoenia sakaeratensis

Levan is a fructose polymer with β-(2 → 6) glycosidic linkages. It is produced by several microorganisms, and due to its potential biotechnological and industrial applications, various levan-producing bacteria with different levels of production efficiencies have been reported. We investigated the levan-producing ability of the acetic acid bacterium, Tanticharoenia sakaeratensis. The exopolysaccharides produced by the bacterium under a sucrose environment were characterized as levan by FT-IR, and ¹H and ¹³C NMR. The molecular weight of levan thus produced range from 1.0 × 10⁵-6.8 × 10⁵ Da. The maximum yield of levan from T. sakaeratensis is 24.7 g·L^-1 in a liquid medium containing 20% (w/v) sucrose and incubated at 37 °C, 250 RPM for 35 h. The levan produced by T. sakaeratensis can promote nitric oxide production in RAW264.7 macrophage cells in a concentration-dependent manner, suggesting it has immunomodulatory effects. Our study reveals that T. sakaeratensis can be potentially employed as a new source of levan for industrial applications.

Synergistic Antimicrobial and Antioxidant Properties of Coccinia grandis (L.) Voigt, Clerodendrum inerme (L.) Gaertn. and Acanthus ebracteatus Vahl. Extracts and Their Potential as a Treatment for Xerosis Cutis

BACKGROUND

A common health condition among older persons is xerosis cutis. Topical corticosteroid treatments are -associated with side effects. There is an unmet need for her-bal treatment alternatives. Coccinia grandis, Clerodendrum inerme and Acanthus ebracteatus are used to treat skin con-ditions in Thai traditional medicine. This study aimed to investigate their antimicrobial and antioxidant properties, synergistic properties as well as their cytotoxicity.

METHODS

-Ethanolic herbal extracts were used to perform minimal -inhibitory (MIC) and minimal bactericidal concentration (MBC) assays on common skin pathogens. Synergistic anti-microbial activity was evaluated by a chequerboard assay. Antioxidant and synergistic properties were assessed by a 1,1-diphenyl-2-picrylhydrazyl assay. Cytotoxicity was tested on normal adult human primary epidermal keratinocytes.

RESULTS

All extracts showed an inhibitory effect on growth of all microorganisms tested. MIC and MBC values ranged from 0.0625 to 32 mg/mL and from 0.0625 to >256 mg/mL, respectively. A. ebracteatus extract markedly demonstrated bactericidal activity against an methicillin-resistant Staphylococcus aureus strain. Additive antimicrobial activity was observed (fractional inhibitory concentration index values: 0.75-1). All extracts possessed antioxidant properties (IC50 values: 0.12-0.25 mg/L). However, antagonism was observed with paired extract combinations (combination index values: 1.025-1.455). The cell viability assay confirmed that herbal extracts were not cytotoxic.

CONCLUSIONS

Our results provide early findings of pharmacological activities to support a novel choice of herbal combinations as potential local skin treatment options for xerosis cutis.

Immunosuppressive effect of hispidulin in allergic contact dermatitis

Background

Long-term use of most immunosuppressants to treat allergic contact dermatitis (ACD) generates unavoidable severe side effects, warranting discovery or development of new immunosuppressants with good efficacy and low toxicity is urgently needed to treat this condition. Hispidulin, a flavonoid compound that can be delivered topically due to its favorable skin penetrability properties, has recently been reported to possess anti-inflammatory and immunosuppressive properties. However, no studies have investigated the effect of hispidulin on Th1 cell activities in an ACD setting.

Methods

A contact hypersensitivity (CHS) mouse model was designed to simulate human ACD. The immunosuppressive effect of hispidulin was investigated via ear thickness, histologic changes (i.e., edema and spongiosis), and interferon-gamma (IFN-γ) gene expression in 1-fluoro-2,4-dinitrobenzene (DNFB)-sensitized mice. Cytotoxicity, total number of CD4⁺ T cells, and percentage of IFN-γ-producing CD4⁺ T cells were also investigated in vitro using isolated CD4⁺ T cells from murine spleens.

Results

Topically applied hispidulin effectively inhibited ear swelling (as measured by reduction in ear thickness), and reduced spongiosis, IFN-γ gene expression, and the number of infiltrated immune cells. The inhibitory effect of hispidulin was observed within 6 h after the challenge, and the observed effects were similar to those effectuated after dexamethasone administration. Hispidulin at a concentration up to 50 μM also suppressed IFN-γ-producing CD4⁺ T cells in a dose-dependent manner without inducing cell death, and without a change in total frequencies of CD4⁺ T cells among different concentration groups.

Conclusion

The results of this study, therefore, suggest hispidulin as a novel compound for the treatment of ACD via the suppression of IFN-γ production in Th1 cells.

RNA-Seq analysis of Clerodendrum inerme (L.) roots in response to salt stress

Background

Clerodendrum inerme (L.) Gaertn, a halophyte, usually grows on coastal beaches as an important mangrove plant. The salt-tolerant mechanisms and related genes of this species that respond to short-term salinity stress are unknown for us. The de novo transcriptome of C. inerme roots was analyzed using next-generation sequencing technology to identify genes involved in salt tolerance and to better understand the response mechanisms of C. inerme to salt stress.

Results

Illumina RNA-sequencing was performed on root samples treated with 400 mM NaCl for 0 h, 6 h, 24 h, and 72 h to investigate changes in C. inerme in response to salt stress. The de novo assembly identified 98,968 unigenes. Among these unigenes, 46,085 unigenes were annotated in the NCBI non-redundant protein sequences (NR) database, 34,756 sequences in the Swiss-Prot database and 43,113 unigenes in the evolutionary genealogy of genes: Non-supervised Orthologous Groups (eggNOG) database. 52 Gene Ontology (GO) terms and 31 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were matched to those unigenes. Most differentially expressed genes (DEGs) related to the GO terms “single-organism process”, “membrane” and “catalytic activity” were significantly enriched while numerous DEGs related to the plant hormone signal transduction pathway were also significantly enriched. The detection of relative expression levels of 9 candidate DEGs by qRT-PCR were basically consistent with fold changes in RNA sequencing analysis, demonstrating that transcriptome data can accurately reflect the response of C. inerme roots to salt stress.

Conclusions

This work revealed that the response of C. inerme roots to saline condition included significant alteration in response of the genes related to plant hormone signaling. Besides, our findings provide numerous salt-tolerant genes for further research to improve the salt tolerance of functional plants and will enhance research on salt-tolerant mechanisms of halophytes.

The Effects of Endocrine Disrupting Chemicals on Biomarkers of Inflammation Produced by Lipopolysaccharide Stimulated RAW264.7 Macrophages

Endocrine disrupting chemicals (EDCs) are common pollutants in the environment and can induce disruption of the endocrine and immune systems. The present study evaluated the effects of selected common environmental EDCs on secretion of inflammatory biomarkers by RAW264.7 cells. The EDCs investigated were Estradiol (E2), 5α-dihydrotestosterone (DHT), and Bisphenol A (BPA). To evaluate if the effects caused by EDCs were modulated by steroid hormone receptors, antagonists of estrogen and androgen receptors were used. The steroid receptor antagonists used were Tamoxifen, an estrogen receptor antagonist, and Flutamide, an androgen receptor antagonist. Secretion of biomarkers of inflammation, namely nitric oxide (NO) and interleukin 6 (IL-6), were monitored. The NO was determined using Griess reaction and IL-6 was measured by enzyme linked immunosorbent assay (ELISA). Although 5 μg/mL E2, DHT, and BPA were not toxic to RAW264.7 cell cultures, the same treatments significantly (p < 0.001) reduced both NO and IL-6 secretion by lipopolysaccharide (LPS)-stimulated RAW264.7 cell cultures. The suppression of NO and IL-6 secretion indicate inhibition of inflammation by DHT, E2, and BPA. The inhibitory effects of DHT, E2 and BPA are partially mediated via their cellular receptors, because the effects were reversed by their respective receptor antagonists. Flutamide reversed the effects of DHT, while Tamoxifen reversed the effects of E2 and BPA. In conclusion, E2, BPA, and DHT inhibit the synthesis of inflammation biomarkers by LPS-stimulated RAW264.7 cells. The inhibitory effects of EDCs can be partially reversed by the addition of an estrogen receptor antagonist for E2 and BPA, and an androgenic receptor antagonist for DHT. The inhibition of inflammatory response in stimulated RAW264.7 cells may be a useful bioassay model for monitoring estrogenic and androgenic pollutants.

Anti-inflammatory effect of trans-4-methoxycinnamaldehyde from Etlingera pavieana in LPS-stimulated macrophages mediated through inactivation of NF-κB and JNK/c-Jun signaling pathways and in rat models of acute inflammation

Trans-4-methoxycinnamaldehyde (MCD) was isolated from the rhizomes of Etlingera pavieana (Pierre ex Gagnep.) R.M.Sm. MCD shows anti-inflammatory effects. However, the molecular mechanism underlying its anti-inflammatory action has not been described. In this study, we investigated this mechanism in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages and found MCD significantly inhibited nitric oxide (NO) and prostaglandin E₂ (PGE₂) production in a concentration-dependent manner. MCD could decrease LPS- and Pam3CSK4- induced the expressions of both iNOS and COX-2. The phosphorylation of inhibitory κB (IκB) and translocation of nuclear factor-κB (NF-κB) p65 subunit into the nucleus were also inhibited by MCD. Moreover, MCD suppressed LPS-induced phosphorylation of JNK except for ERK and p38 mitogen-activated protein kinases (MAPKs). Moreover, MCD significantly reduced ethyl phenylpropiolate-induced ear edema and carrageenan-induced paw edema in rat models. These findings indicated MCD has anti-inflammatory activity by inhibiting the production of NO and PGE₂ by blocking NF-κB and JNK/c-Jun signaling pathways. Collectively, these data suggest that MCD could be developed as a novel therapeutic agent for inflammatory disorders.

Antioxidant and anti-inflammatory effects of polyphenols extracted from Ilex latifolia Thunb

To promote the rational and effective application of Ilex latifolia Thunb., a Chinese bitter tea widely consumed as a health beverage, polyphenols were extracted from its leaves and their cellular antioxidant activity (CAA) and anti-inflammatory effect against mouse macrophage RAW 264.7 cells were analyzed. Results showed that the antioxidant capacity of polyphenols was high, and their CAA values in PBS wash and no PBS wash protocols were 6871.42 ± 85.56 and 25161.61 ± 583.55 μmol QE (quercetin equivalents)/100 g phenolic extracts, respectively. In addition, polyphenols from I. latifolia displayed strong inhibition on LPS-induced NO-production in RAW 264.7 cells. Polyphenol treatment inhibited the release of pro-inflammatory cytokines (TNF-α, IL-1β and IL-6) induced by LPS in a dose-dependent manner by ELISA and mRNA expression analysis. Western blot results showed that the anti-inflammatory activity of polyphenols from I. latifolia might be exerted through inhibiting the activation of MAPKs (ERK and JNK) and NF-κB to decrease NO, COX-2 and pro-inflammatory cytokines production. Thus, the polyphenol enriched extracts from I. latifolia are a good source of natural antioxidants with a beneficial effect against inflammation, and they may be applied as a food supplement and/or functional ingredient.

Biocompatible zwitterionic copolymer-stabilized magnetite nanoparticles: a simple one-pot synthesis, antifouling properties and biomagnetic separation

A simple one-pot synthesis of biocompatible and antifouling magnetite nanoparticles (Fe₃O₄NPs) was developed. The process involves co-precipitation and in situ coating of zwitterionic copolymer poly[(methacrylic acid)-co-(2-methacryloyloxyethyl phosphorylcholine)] (PMAMPC). The influence of one-step and two-step coating methods on the performance of modified Fe₃O₄NP was investigated. The PMAMPC-Fe₃O₄NP with a narrow particle size distribution obtained from the two-step approach were highly stable in aqueous media within a wide range of pH. The particles exhibited superparamagnetic behavior with high saturation magnetization values so that they could be easily separated from solution by a magnet. Their antifouling characteristics against 2 selected proteins, lysozyme (LYZ) and bovine serum albumin (BSA), as a function of copolymer molecular weight and composition were also evaluated. Moreover, taking advantage of having carboxyl groups in the coated copolymer, the PMAMPC-Fe₃O₄NP were conjugated with a model biomolecular probe, biotin. The biotin-immobilized PMAMPC-Fe₃O₄NP were then tested for their specific capturing of a target molecule, streptavidin. The results have demonstrated the potential of PMAMPC-Fe₃O₄NP prepared by the two-step in situ coating method for probe immobilization and subsequent biomagnetic separation of target molecules. The fact that the developed functionalizable magnetite nanoparticles are biocompatible and antifouling also opens up the possibility of their use in other biomedical-relevant applications.

A simple one-pot synthesis of biocompatible and antifouling magnetite nanoparticles (Fe₃O₄NPs) was developed.

Non-cytotoxic hybrid bioscaffolds of chitosan-silica: Sol-gel synthesis, characterization and proposed application

Biohybrid chitosan-silica scaffolds were synthesized through the sol-gel and the freeze drying processes. Hydrolysis and condensation of chitosan with tetraethylorthosilicate (TEOS) in the presence of 3-isocyanatopropyl triethoxysilane (ICPTES) were successfully carried out. Results obtained from FTIR, swelling test and pyrolysis confirmed that the hybrid scaffolds containing covalent coupling between the organic and inorganic networks were formed with high crosslink density of SiOSi bridging and could be classified as the class II material. The hybridization also resulted in improvements on mechanical strength and stability comparing to the pure chitosan. In vitro investigations on the guided bone regeneration and the cytotoxicity were also performed. SEM-EDS was used to examine the proliferation of calcium phosphate mineral at the scaffold surface after an immersion in simulated body fluid. The results revealed that the hybrid scaffolds exhibited a rapid induction of calcium phosphate mineral without cytotoxicity effect, reflecting an excellent in vitro bone bioactivity which was superior to the pure chitosan scaffold.

Traditional uses and pharmacological properties of Clerodendrum phytochemicals

Clerodendrum is a genus of ca. 500 species in the family Lamiaceae and widely distributed throughout the whole world. Up to now, many species of this genus have been described in various indigenous systems of medicine and are used in preparation of folklore medicines for the treatment of various life-threatening diseases, and more than eleven species of the Clerodendrum genus have been very well studied for their chemical constituents and biological activities, and 283 compounds, including monoterpene and its derivatives, sesquiterpene, diterpenoids, triterpenoids, flavonoid and flavonoid glycosides, phenylethanoid glycosides, steroids and steroid glycosides, cyclohexylethanoids, anthraquinones, cyanogenic glycosides, and others have been isolated and identified. Pharmacological studies have shown that these compounds and extracts from the Clerodendrum genus have extensive activities, such as anti-inflammatory and anti-nociceptive, anti-oxidant, anti-hypertensive, anticancer, antimicrobial, anti-diarrheal, hepatoprotective, hypoglycemic and hypolipidemic, memory enhancing and neuroprotective, and other activities. In this review, we attempt to highlight over phytochemical progress and list the phytoconstituents isolated from the genus Clerodendrum reported so far. The biological activities of this genus are also covered.

Role of Antioxidants and Natural Products in Inflammation

Inflammation is a comprehensive array of physiological response to a foreign organism, including human pathogens, dust particles, and viruses. Inflammations are mainly divided into acute and chronic inflammation depending on various inflammatory processes and cellular mechanisms. Recent investigations have clarified that inflammation is a major factor for the progression of various chronic diseases/disorders, including diabetes, cancer, cardiovascular diseases, eye disorders, arthritis, obesity, autoimmune diseases, and inflammatory bowel disease. Free radical productions from different biological and environmental sources are due to an imbalance of natural antioxidants which further leads to various inflammatory associated diseases. In this review article, we have outlined the inflammatory process and its cellular mechanisms involved in the progression of various chronic modern human diseases. In addition, we have discussed the role of free radicals-induced tissue damage, antioxidant defence, and molecular mechanisms in chronic inflammatory diseases/disorders. The systematic knowledge regarding the role of inflammation and its associated adverse effects can provide a clear understanding in the development of innovative therapeutic targets from natural sources that are intended for suppression of various chronic inflammations associated diseases.

In Vitro Propagation, Phytochemical Analysis, and Evaluation of Free Radical Scavenging Property of Scrophularia kakudensis Franch Tissue Extracts

The current study deals with in vitro propagation, antioxidant property estimation, and assessment of acacetin content in Scrophularia kakudensis Franch. Adventitious shoot induction was achieved from the nodal explant with the highest number of adventitious shoots per explant (17.4) on Murashige and Skoog's (MS) medium fortified with 2.0 mg·L(-1) 6-benzyladenine (BA) and 0.5 mg L(-1) indole-3-acetic acid (IAA). Maximum number of roots per plant (16.5) was noted in half strength MS medium supplemented with 0.5 mg·L(-1) IAA. The regenerated plants displayed successful survival ratio (95%) in the greenhouse. The highest content of acacetin, a pharmaceutically important flavonoid, was observed in the shoot extracts (in vitro: 32.83 µg·g(-1) FW; in vivo: 30.05 µg·g(-1) FW) followed by root extracts. Total phenol and flavonoid contents along with free radical scavenging assays revealed the occurrence of larger amount of antioxidants in shoot extract in comparison with callus and root extracts of S. kakudensis. Thus, the outcome of the present study can be highly beneficial for the germplasm conservation and commercial cultivation of S. kakudensis for therapeutic purposes.