New Findings Regarding the Effects of Selected Blue Food Colorants (Genipin, Patent Blue V, and Brilliant Blue FCF) on the Hemostatic Properties of Blood Components In Vitro.

Natural and synthetic colorants present in food can modulate hemostasis, which includes the coagulation process and blood platelet activation. Some colorants have cardioprotective activity as well. However, the effect of genipin (a natural blue colorant) and synthetic blue colorants (including patent blue V and brilliant blue FCF) on hemostasis is not clear. In this study, we aimed to investigate the effects of three blue colorants-genipin, patent blue V, and brilliant blue FCF-on selected parameters of hemostasis in vitro. The anti- or pro-coagulant potential was assessed in human plasma by measuring the following coagulation times: thrombin time (TT), prothrombin time (PT), and activated partial thromboplastin time (APTT). Moreover, we used the Total Thrombus formation Analysis System (T-TAS, PL-chip) to evaluate the anti-platelet potential of the colorants in whole blood. We also measured their effect on the adhesion of washed blood platelets to fibrinogen and collagen. Lastly, the cytotoxicity of the colorants against blood platelets was assessed based on the activity of extracellular lactate dehydrogenase (LDH). We observed that genipin (at all concentrations (1-200 µM)) did not have a significant effect on the coagulation times (PT, APTT, and TT). However, genipin at the highest concentration (200 µM) and patent blue V at the concentrations of 1 and 10 µM significantly prolonged the time of occlusion measured using the T-TAS, which demonstrated their anti-platelet activity. We also observed that genipin decreased the adhesion of platelets to fibrinogen and collagen. Only patent blue V and brilliant blue FCF significantly shortened the APTT (at the concentration of 10 µM) and TT (at concentrations of 1 and 10 µM), demonstrating pro-coagulant activity. These synthetic blue colorants also modulated the process of human blood platelet adhesion, stimulating the adhesion to fibrinogen and inhibiting the adhesion to collagen. The results demonstrate that genipin is not toxic. In addition, because of its ability to reduce blood platelet activation, genipin holds promise as a novel and valuable agent that improves the health of the cardiovascular system and reduces the risk of cardiovascular diseases. However, the mechanism of its anti-platelet activity remains unclear and requires further studies. Its in vivo activity and interaction with various anti-coagulant and anti-thrombotic drugs, including aspirin and its derivatives, should be examined as well.

IL-17A Drives Oxidative Stress and Cell Growth in A549 Lung Epithelial Cells: Potential Protective Action of Oleuropein.

IL-17A drives inflammation and oxidative stress, affecting the progression of chronic lung diseases (asthma, chronic obstructive pulmonary disease (COPD), lung cancer, and cystic fibrosis). Oleuropein (OLP) is a polyphenolic compound present in olive oil and widely included in the Mediterranean diet. It exerts antioxidant and anti-inflammatory activities, oxidative stress resistance, and anticarcinogenic effects with a conceivable positive impact on human health. We hypothesized that OLP positively affects the mechanisms of oxidative stress, apoptosis, DNA damage, cell viability during proliferation, and cell growth in alveolar epithelial cells and tested its effect in a human alveolar epithelial cell line (A549) in the presence of IL-17A. Our results show that OLP decreases the levels of oxidative stress (Reactive Oxygen Species, Mitochondrial membrane potential) and DNA damage (H2AX phosphorylation-ser139, Olive Tail Moment data) and increases cell apoptosis in A549 cells exposed to IL-17A. Furthermore, OLP decreases the number of viable cells during proliferation, the migratory potential (Scratch test), and the single cell capacity to grow within colonies as a cancer phenotype in A549 cells exposed to IL-17A. In conclusion, we suggest that OLP might be useful to protect lung epithelial cells from oxidative stress, DNA damage, cell growth, and cell apoptosis. This effect might be exerted in lung diseases by the downregulation of IL-17A activities. Our results suggest a positive effect of the components of olive oil on human lung health.

Biofunctionalized hydrogel composed of genipin-crosslinked gelatin/hyaluronic acid incorporated with lyophilized platelet-rich fibrin for segmental bone defect repair.

Segmental bone defects can arise from trauma, infection, metabolic bone disorders, or tumor removal. Hydrogels have gained attention in the field of bone regeneration due to their unique hydrophilic properties and the ability to customize their physical and chemical characteristics to serve as scaffolds and carriers for growth factors. However, the limited mechanical strength of hydrogels and the rapid release of active substances have hindered their clinical utility and therapeutic effectiveness. With ongoing advancements in material science, the development of injectable and biofunctionalized hydrogels holds great promise for addressing the challenges associated with segmental bone defects. In this study, we incorporated lyophilized platelet-rich fibrin (LPRF), which contains a multitude of growth factors, into a genipin-crosslinked gelatin/hyaluronic acid (GLT/HA-0.5 % GP) hydrogel to create an injectable and biofunctionalized composite material. Our findings demonstrate that this biofunctionalized hydrogel possesses optimal attributes for bone tissue engineering. Furthermore, results obtained from rabbit model with segmental tibial bone defects, indicate that the treatment with this biofunctionalized hydrogel resulted in increased new bone formation, as confirmed by imaging and histological analysis. From a translational perspective, this biofunctionalized hydrogel provides innovative and bioinspired capabilities that have the potential to enhance bone repair and regeneration in future clinical applications.

Plumieride as a novel anti-fungal and anti-inflammatory iridoid against superficial candidiasis in mice.

In the past few decades, there has been a notable rise in the occurrence of several types of candidiasis. Candida albicans is the most common cause of superficial fungal infections in humans. In this study, plumieride, one of the major iridoids from Plumeria obtusa L. leaves, was isolated and investigated for its potential against Candida albicans (CA)-induced dermatitis in mice. qRT-PCR was done to assess the impact of plumieride on the expression of the major virulence genes of CA. Five groups (n = 7) of adult male BALB/c mice were categorized into: group I: non-infected mice; group II: mice infected intradermally with 107-108 CFU/mL of CA; group III: CA-infected mice treated with standard fluconazole (50 mg/kg bwt.); group IV and V: CA-infected mice treated with plumieride (25- and 50 mg/kg. bwt., respectively). All the treatments were subcutaneously injected once a day for 3 days. Skin samples were collected on the 4th day post-inoculation to perform pathological, microbial, and molecular studies. The results of the in vitro study proved that plumieride has better antifungal activity than fluconazole, manifested by a wider zone of inhibition and a lower MIC. Plumieride also downregulated the expression of CA virulence genes (ALS1, Plb1, and Hyr1). CA-infected mice showed extensive dermatitis, confirmed by strong iNOS, TNF-α, IL-1ß, and NF-κB genes or immune expressions. Whereas the treatment of CA-infected mice with plumieride significantly reduced the microscopic skin lesions and modulated the expression of all measured proinflammatory cytokines and inflammatory markers in a dose-dependent manner. Plumieride interfered with the expression of C. albicans virulence factors and modulated the inflammatory response in the skin of mice infected with CA.

Genipin's potential as an anti-cancer agent: from phytochemical origins to clinical prospects.

This comprehensive review delves into the multifaceted aspects of genipin, a bioactive compound derived from medicinal plants, focusing on its anti-cancer potential. The review begins by detailing the sources and phytochemical properties of genipin, underscoring its significance in traditional medicine and its transition into contemporary cancer research. It then explores the intricate relationship between genipin's chemical structure and its observed anti-cancer activity, highlighting the molecular underpinnings contributing to its therapeutic potential. This is complemented by a thorough analysis of preclinical studies, which investigates genipin's efficacy against various cancer cell lines and its mechanisms of action at the cellular level. A crucial component of the review is the examination of genipin's bioavailability and pharmacokinetics, providing insights into how the compound is absorbed, distributed, metabolized, and excreted in the body. Then, this review offers a general and updated overview of the anti-cancer studies of genipin and its derivatives based on its basic molecular mechanisms, induction of apoptosis, inhibition of cell proliferation, and disruption of cancer cell signaling pathways. We include information that complements the genipin study, such as toxicity data, and we differentiate this review by including commercial status, disposition, and regulation. Also, this review of genipin stands out for incorporating information on proposals for a technological approach through its load in nanotechnology to improve its bioavailability. The culmination of this information positions genipin as a promising candidate for developing novel anti-cancer drugs capable of supplementing or enhancing current cancer therapies.

Monotropein mitigates atopic dermatitis-like skin inflammation through JAK/STAT signaling pathway inhibition.

Atopic dermatitis (AD) is a globally increasing chronic inflammatory skin disease with limited and potentially side-effect-prone treatment options. Monotropein is the predominant iridoid glycoside in Morinda officinalis How roots, which has previously shown promise in alleviating AD symptoms. This study aimed to systematically investigate the pharmacological effects of monotropein on AD using a 2, 4-dinitrochlorobenzene (DNCB)/Dermatophagoides farinae extract (DFE)-induced AD mice and tumor necrosis factor (TNF)-α/interferon (IFN)-γ-stimulated keratinocytes. Oral administration of monotropein demonstrated a significant reduction in AD phenotypes, including scaling, erythema, and increased skin thickness in AD-induced mice. Histological analysis revealed a marked decrease in immune cell infiltration in skin lesions. Additionally, monotropein effectively downregulated inflammatory markers, encompassing pro-inflammatory cytokines, T helper (Th)1 and Th2 cytokines, and pro-inflammatory chemokines in skin tissues. Notably, monotropein also led to a considerable decrease in serum immunoglobulin (Ig)E and IgG2a levels. At a mechanistic level, monotropein exerted its anti-inflammatory effects by suppressing the phosphorylation of Janus kinase / signal transducer and activator of transcription proteins in both skin tissues of AD-induced mice and TNF-α/IFN-γ-stimulated keratinocytes. In conclusion, monotropein exhibited a pronounced alleviation of AD symptoms in the experimental models used. These findings underscore the potential application of monotropein as a therapeutic agent in the context of AD, providing a scientific basis for further exploration and development.

Effect of Oleuropein on Anti-Obesity and Uncoupling Protein 1 Level in Brown Adipose Tissue in Mild Treadmill Walking Rats with Diet-Induced Obesity.

Oleuropein aglycone (OA), which is the absorbed form of oleuropein, is a major phenolic compound in extra virgin olive oil. We analyzed the anti-obesity effect of OA intake combined with mild treadmill walking (MTW, 4 m/min for 20 min/d, 5-6 d/wk, without electric shocks and slope) in rats under a high-fat diet (HF). Four-week-old male Sprague-Dawley rats (n=28) were equally divided into four groups: control (HF), 0.08% oleuropein-supplemented HF (HFO), HF with MTW (HF+W), and HFO with MTW (HFO+W) groups. After 28 d, the inguinal subcutaneous fat content and weight gain were significantly lower in the HFO+W group than in the control group. The HFO+W group also had significantly higher levels of urinary noradrenaline secretion, interscapular brown adipose tissue, uncoupling protein 1, brain transient receptor potential ankyrin subtype 1 (TRPA1), vanilloid subtype 1 (TRPV1), and brain-derived neurotrophic factor (BDNF) than the control group. Especially, the HFO+W group showed a synergistic effect on noradrenaline secretion. Therefore, OA combined with MTW may accelerate the enhancement of UCP1 and BDNF levels in rats with HF-induced obesity by increasing noradrenaline secretion after TRPA1 and TRPV1 activation.

Oleuropein, a Component of Extra Virgin Olive Oil, Improves Liver Steatosis and Lobular Inflammation by Lipopolysaccharides-TLR4 Axis Downregulation.

Gut-dysbiosis-induced lipopolysaccharides (LPS) translocation into systemic circulation has been suggested to be implicated in nonalcoholic fatty liver disease (NAFLD) pathogenesis. This study aimed to assess if oleuropein (OLE), a component of extra virgin olive oil, lowers high-fat-diet (HFD)-induced endotoxemia and, eventually, liver steatosis. An immunohistochemistry analysis of the intestine and liver was performed in (i) control mice (CTR; n = 15), (ii) high-fat-diet fed (HFD) mice (HFD; n = 16), and (iii) HFD mice treated with 6 µg/day of OLE for 30 days (HFD + OLE, n = 13). The HFD mice developed significant liver steatosis compared to the controls, an effect that was significantly reduced in the HFD + OLE-treated mice. The amount of hepatocyte LPS localization and the number of TLR4+ macrophages were higher in the HFD mice in the than controls and were lowered in the HFD + OLE-treated mice. The number of CD42b+ platelets was increased in the liver sinusoids of the HFD mice compared to the controls and decreased in the HFD + OLE-treated mice. Compared to the controls, the HFD-treated mice showed a high percentage of intestine PAS+ goblet cells, an increased length of intestinal crypts, LPS localization and TLR4+ expression, and occludin downregulation, an effect counteracted in the HFD + OLE-treated mice. The HFD-fed animals displayed increased systemic levels of LPS and zonulin, but they were reduced in the HFD + OLE-treated animals. It can be seen that OLE administration improves liver steatosis and inflammation in association with decreased LPS translocation into the systemic circulation, hepatocyte localization of LPS and TLR4 downregulation in HFD-induced mouse model of NAFLD.

Near-infrared-II responsive ovalbumin functionalized gold-genipin nanosystem cascading photo-immunotherapy of cancer.

Synergistic cancer therapies have attracted wide attention owing to their multi-mode tumor inhibition properties. Especially, photo-responsive photoimmunotherapy demonstrates an emerging cancer treatment paradigm that significantly improved treatment efficiency. Herein, near-infrared-II responsive ovalbumin functionalized Gold-Genipin nanosystem (Au-G-OVA NRs) was designed for immunotherapy and deep photothermal therapy of breast cancer. A facile synthesis method was employed to prepare the homogeneous Au nanorods (Au NRs) with good dispersion. The nanovaccine was developed further by the chemical cross-linking of Au-NRs, genipin and ovalbumin. The Au-G-OVA NRs outstanding aqueous solubility, and biocompatibility against normal and cancer cells. The designed NRs possessed enhanced localized surface plasmon resonance (LSPR) effect, which extended the NIR absorption in the second window, enabling promising photothermal properties. Moreover, genipin coating provided complimentary red fluorescent and prepared Au-G-OVA NRs showed significant intracellular encapsulation for efficient photoimmunotherapy outcomes. The designed nanosystem possessed deep photothermal therapy of breast cancer and 90% 4T1 cells were ablated by Au-G-OVA NRs (80µg ml-1concentration) after 1064 nm laser irradiation. In addition, Au-G-OVA NRs demonstrated outstanding vaccination phenomena by facilitating OVA delivery, antigen uptake, maturation of bone marrow dendritic cells, and cytokine IFN-γsecretion for tumor immunosurveillance. The aforementioned advantages permit the utilization of fluorescence imaging-guided photo-immunotherapy for cancers, demonstrating a straightforward approach for developing nanovaccines tailored to precise tumor treatment.

Ptehosides A-I: Nine undescribed iridoids with in vitro cytotoxicity from the whole plant of Pterocephalus hookeri (C.B. Clarke) Höeck.

Nine previously undescribed iridoids, ptehosides A-I (1-9), together with 12 known ones (10-21), were isolated from Pterocephalus hookeri (C.B. Clarke) Höeck. Their structures were elucidated using various spectroscopic methods including HR-ESI-MS, NMR, UV, IR and CD, etc. The cytotoxic activities of all isolates were evaluated using MTT method in three human cancer cell lines (Caco2, Huh-7, and SW982). As result, compound 9 exhibited substantial inhibitory activity on Caco2, Huh-7, and SW982 cells with IC50 values of 1.17 ± 0.05, 1.15 ± 0.05 and 1.14 ± 0.04 µM, respectively. A preliminary mechanism study showed that 9 arrested the cell cycle of SW982 cells in the G0/G1 phase and induced apoptosis by upregulating Bax expression and downregulating Bcl-2 expression.

Modulation of Decellularized Lacrimal Gland Hydrogel Biodegradation by Genipin Crosslinking.

Purpose: Hydrogels derived from decellularized tissues are promising biomaterials in tissue engineering, but their rapid biodegradation can hinder in vitro cultivation. This study aimed to retard biodegradation of a hydrogel derived from porcine decellularized lacrimal glands (dLG-HG) by crosslinking with genipin to increase the mechanical stability without affecting the function and viability of lacrimal gland (LG)-associated cells. Methods: The effect of different genipin concentrations on dLG-HG stiffness was measured rheologically. Cell-dependent biodegradation was quantified over 10 days, and the impact on matrix metalloproteinase (MMP) activity was quantified by gelatin and collagen zymography. The viability of LG epithelial cells (EpCs), mesenchymal stem cells (MSCs), and endothelial cells (ECs) cultured on genipin-crosslinked dLG-HG was assessed after 10 days, and EpC secretory activity was analyzed by ß-hexosaminidase assay. Results: The 0.5-mM genipin increased the stiffness of dLG-HG by about 46%, and concentrations > 0.25 mM caused delayed cell-dependent biodegradation and reduced MMP activity. The viability of EpCs, MSCs, and ECs was not affected by genipin concentrations of up to 0.5 mM after 10 days. Moreover, up to 0.5-mM genipin did not negatively affect EpC secretory activity compared to control groups. Conclusions: A concentration of 0.5-mM genipin increased dLG-HG stiffness, and 0.25-mM genipin was sufficient to prevent MMP-dependent degradation. Importantly, concentrations of up to 0.5-mM genipin did not compromise the viability of LG-associated cells or the secretory activity of EpCs. Thus, crosslinking with genipin improves the properties of dLG-HG for use as a substrate in LG tissue engineering.

Antimicrobial and anti-biofilm properties of oleuropein against Escherichia coli and fluconazole-resistant isolates of Candida albicans and Candida glabrata.

BACKGROUND: Side effects associated with antimicrobial drugs, as well as their high cost, have prompted a search for low-cost herbal medicinal substances with fewer side effects. These substances can be used as supplements to medicine or to strengthen their effects. The current study investigated the effect of oleuropein on the inhibition of fungal and bacterial biofilm in-vitro and at the molecular level. MATERIALS AND METHODS: In this experimental study, antimicrobial properties were evaluated using microbroth dilution method. The effect of oleuropein on the formation and eradication of biofilm was assessed on 96-well flat bottom microtiter plates and their effects were observed through scanning electron microscopy (SEM). Its effect on key genes (Hwp1, Als3, Epa1, Epa6, LuxS, Pfs) involved in biofilm formation was investigated using the quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR) method. RESULTS: The minimum inhibitory concentration (MIC) and minimum fungicidal/bactericidal concentration (MFC/MBC) for oleuropein were found to be 65 mg/ml and 130 mg/ml, respectively. Oleuropein significantly inhibited biofilm formation at MIC/2 (32.5 mg/ml), MIC/4 (16.25 mg/ml), MIC/8 (8.125 mg/ml) and MIC/16 (4.062 mg/ml) (p < 0.0001). The anti-biofilm effect of oleuropein was confirmed by SEM. RT-qPCR indicated significant down regulation of expression genes involved in biofilm formation in Candida albicans (Hwp1, Als3) and Candida glabrata (Epa1, Epa6) as well as Escherichia coli (LuxS, Pfs) genes after culture with a MIC/2 of oleuropein (p < 0.0001). CONCLUSIONS: The results indicate that oleuropein has antifungal and antibacterial properties that enable it to inhibit or destroy the formation of fungal and bacterial biofilm.

Discovery, optimization and biological activity evaluation of genipin derivatives as potential KRAS G12D inhibitors.

A series of genipin derivatives were designed and synthesized as potential inhibitors targeted KRAS G12D mutation. The majority of these compounds demonstrated potential antiproliferative effects against KRAS G12D mutant tumor cells (CT26 and A427). Notably, seven compounds exhibited the anticancer effects with IC50 values ranging from 7.06 to 9.21 µM in CT26 (KRASG12D) and A427 (KRASG12D) cells and effectively suppressed the colony formation of CT26 cells. One representative compound SK12 was selected for further investigation into biological activity and action mechanisms. SK12 markedly induced apoptosis in CT26 cells in a concentration-dependent manner. Moreover, SK12 elevated the levels of reactive oxygen species (ROS) in tumor cells and exhibited a modulatory effect on the KRAS signaling pathway, thereby inhibiting the activation of downstream phosphorylated proteins. The binding affinity of SK12 to KRAS G12D protein was further confirmed by the surface plasmon resonance (SPR) assay with a binding KD of 157 µM. SK12 also exhibited notable anticancer efficacy in a nude mice tumor model. The relative tumor proliferation rate (T/C) of the experimental group (50 mg/kg) was 31.04 % (P < 0.05), while maintaining a commendable safety profile.

Genipin improves obesity through promoting bile secretion and changing bile acids composition in diet-induced obese rats.

OBJECTIVES: Bile acids (BAs), as signaling molecules to regulate metabolism, have received considerable attention. Genipin is an iridoid compound extracted from Fructus Gradeniae, which has been shown to relieve adiposity and metabolic syndrome. Here, we investigated the mechanism of genipin counteracting obesity and its relationship with BAs signals in diet-induced obese (DIO) rats. METHODS: The DIO rats were received intraperitoneal injections of genipin for 10 days. The body weight, visceral fat, lipid metabolism in the liver, thermogenic genes expressions in brown fat, BAs metabolism and signals, and key enzymes for BAs synthesis were determined. KEY FINDINGS: Genipin inhibited fat synthesis and promoted lipolysis in the liver, and upregulated thermogenic gene expressions in brown adipose tissue of DIO rats. Genipin increased bile flow rate and upregulated the expressions of aquaporin 8 and the transporters of BAs in liver. Furthermore, genipin changed BAs composition by promoting alternative pathways and inhibiting classical pathways for BAs synthesis and upregulated the expressions of bile acid receptors synchronously. CONCLUSIONS: These results suggest that genipin ameliorate obesity through BAs-mediated signaling pathways.

Genipin Activates Autophagy and Promotes Myoblast Differentiation by Activating AMPK Pathway.

Cultured meat technology is expected to solve problems such as resource shortages and environmental pollution, but the muscle fiber differentiation efficiency of cultured meat is low. Genipin is the active compound derived from Gardenia jasminoides Ellis, which has a variety of activities. Additionally, genipin serves as a noncytotoxic agent for cross-linking, which is suitable as a foundational scaffold for in vitro tissue regeneration. However, the impact of genipin on myoblast differentiation remains to be studied. The research revealed that genipin was found to improve the differentiation efficiency of myoblasts. Genipin improved mitochondrial membrane potential by activating the AMPK signaling pathway of myoblasts, promoting mitochondrial biogenesis, and mitochondrial network remodeling. Genipin activated autophagy in myoblasts and maintained cellular homeostasis. Autophagy inhibitors blocked the pro-differentiation effect of genipin. These results showed that genipin improved the differentiation efficiency of myoblasts, which provided a theoretical basis for the development of cultured meat technology.

Geniposide and Harpagoside Functionalized Cerium Oxide Nanoparticles as a Potential Neuroprotective.

Alzheimer's disease is associated with protein aggregation, oxidative stress, and the role of acetylcholinesterase in the pathology of the disease. Previous investigations have demonstrated that geniposide and harpagoside protect the brain neurons, and cerium nanoparticles (CeO2 NPs) have potent redox and antioxidant properties. Thus, the effect of nanoparticles of Ce NPs and geniposide and harpagoside (GH/CeO2 NPs) on ameliorating AD pathogenesis was established on AlCl3-induced AD in mice and an aggregation proteins test in vitro. Findings of spectroscopy analysis have revealed that GH/CeO2 NPs are highly stable, nano-size, spherical in shape, amorphous nature, and a total encapsulation of GH in cerium. Treatments with CeO2 NPs, GH/CeO2 NPs, and donepezil used as positive control inhibit fibril formation and protein aggregation, protect structural modifications in the BSA-ribose system, have the ability to counteract Tau protein aggregation and amyloid-ß1-42 aggregation under fibrillation condition, and are able to inhibit AChE and BuChE. While the GH/CeO2 NPs, treatment in AD induced by AlCl3 inhibited amyloid-ß1-42, substantially enhanced the memory, the cognition coordination of movement in part AD pathogenesis may be alleviated through reducing amyloidogenic pathway and AChE and BuChE activities. The findings of this work provide important comprehension of the chemoprotective activities of iridoids combined with nanoparticles. This could be useful in the development of new therapeutic methods for the treatment of neurodegenerative diseases.

Comparative Analysis of Olive-Derived Phenolic Compounds' Pro-Melanogenesis Effects on B16F10 Cells and Epidermal Human Melanocytes.

Olive leaf contains plenty of phenolic compounds, among which oleuropein (OP) is the main component and belongs to the group of secoiridoids. Additionally, phenolic compounds such as oleocanthal (OL) and oleacein (OC), which share a structural similarity with OP and two aldehyde groups, are also present in olive leaves. These compounds have been studied for several health benefits, such as anti-cancer and antioxidant effects. However, their impact on the skin remains unknown. Therefore, this study aims to compare the effects of these three compounds on melanogenesis using B16F10 cells and human epidermal cells. Thousands of gene expressions were measured by global gene expression profiling with B16F10 cells. We found that glutaraldehyde compounds derived from olive leaves have a potential effect on the activation of the melanogenesis pathway and inducing differentiation in B16F10 cells. Accordingly, the pro-melanogenesis effect was investigated by means of melanin quantification, mRNA, and protein expression using human epidermal melanocytes (HEM). This study suggests that secoiridoid and its derivates have an impact on skin protection by promoting melanin production in both human and mouse cell lines.

In vitro biological evaluation and in silico insights into the antiviral activity of standardized olive leaves extract against SARS-CoV-2.

There is still a great global need for efficient treatments for the management of SARS-CoV-2 illness notwithstanding the availability and efficacy of COVID-19 vaccinations. Olive leaf is an herbal remedy with a potential antiviral activity that could improve the recovery of COVID-19 patients. In this work, the olive leaves major metabolites were screened in silico for their activity against SARS-CoV-2 by molecular docking on several viral targets such as methyl transferase, helicase, Plpro, Mpro, and RdRp. The results of in silico docking study showed that olive leaves phytoconstituents exhibited strong potential antiviral activity against SARS-CoV-2 selected targets. Verbacoside demonstrated a strong inhibition against methyl transferase, helicase, Plpro, Mpro, and RdRp (docking scores = -17.2, -20, -18.2, -19.8, and -21.7 kcal/mol.) respectively. Oleuropein inhibited 5rmm, Mpro, and RdRp (docking scores = -15, -16.6 and -18.6 kcal/mol., respectively) respectively. Apigenin-7-O-glucoside exhibited activity against methyl transferase and RdRp (docking score = -16.1 and -19.4 kcal/mol., respectively) while Luteolin-7-O-glucoside inhibited Plpro and RdRp (docking score = -15.2 and -20 kcal/mol., respectively). The in vitro antiviral assay was carried out on standardized olive leaf extract (SOLE) containing 20% oleuropein and IC50 was calculated. The results revealed that 20% SOLE demonstrated a moderate antiviral activity against SARS-CoV-2 with IC50 of 118.3 µg /mL. Accordingly, olive leaf could be a potential herbal therapy against SARS-CoV-2 but more in vivo and clinical investigations are recommended.

Study on the Neuroprotective Effects of Eight Iridoid Components Using Cell Metabolomics.

Iridoid components have been reported to have significant neuroprotective effects. However, it is not yet clear whether the efficacy and mechanisms of iridoid components with similar structures are also similar. This study aimed to compare the neuroprotective effects and mechanisms of eight iridoid components (catalpol (CAT), genipin (GE), geniposide (GEN), geniposidic acid (GPA), aucubin (AU), ajugol (AJU), rehmannioside C (RC), and rehmannioside D (RD)) based on corticosterone (CORT)-induced injury in PC12 cells. PC12 cells were randomly divided into a normal control group (NC), model group (M), positive drug group (FLX), and eight iridoid administration groups. Firstly, PC12 cells were induced with CORT to simulate neuronal injury. Then, the MTT method and flow cytometry were applied to evaluate the protective effects of eight iridoid components on PC12 cell damage. Thirdly, a cell metabolomics study based on ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q/TOF-MS) was performed to explore changes in relevant biomarkers and metabolic pathways following the intervention of administration. The MTT assay and flow cytometry analysis showed that the eight iridoid components can improve cell viability, inhibit cell apoptosis, reduce intracellular ROS levels, and elevate MMP levels. In the PCA score plots, the sample points of the treatment groups showed a trend towards approaching the NC group. Among them, AU, AJU, and RC had a weaker effect. There were 38 metabolites (19 metabolites each in positive and negative ion modes, respectively) identified as potential biomarkers during the experiment, among which 23 metabolites were common biomarkers of the eight iridoid groups. Pathway enrichment analysis revealed that the eight iridoid components regulated the metabolism mainly in relation to D-glutamine and D-glutamate metabolism, arginine biosynthesis, the TCA cycle, purine metabolism, and glutathione metabolism. In conclusion, the eight iridoid components could reverse an imbalanced metabolic state by regulating amino acid neurotransmitters, interfering with amino acid metabolism and energy metabolism, and harmonizing the level of oxidized substances to exhibit neuroprotective effects.

Geniposide alleviates imiquimod-induced psoriasis-like skin lesions in mice via inhibition of angiogenesis.

In this study, we aimed to evaluate the protective effect of geniposide (GEN) on imiquimod (IMQ)-induced psoriasis-like skin lesions in mice. Firstly, visual changes of psoriatic skin lesions were observed and the severity was recorded using psoriasis area and severity index (PASI) score. Histological changes were assessed by HE staining for epidermal thickness and Masson's staining for collagen fibers. Then, photographs of microvascular inside the skin were taken for macroscopic observation, and microscopic changes associated with angiogenesis were evaluated. Furthermore, expression of angiogenic factors were analyzed by ELISA, immunohistochemistry and immunofluorescence, separately. Lastly, the expression of VEGFR signaling-related proteins was detected by WB. Compared with control, IMQ drove a significant increment of epidermal thicknesses with higher PASI scores and more dermal collagen deposition. IMQ treatment led to abnormal keratinocyte proliferation, increased microvascular inside skin, growing production of angiogenesis-related factors, up-regulated expression of VEGFR1 and VEGFR2, and enhanced phosphorylation of p38. However, GEN significantly ameliorated the psoriatic skin lesions, the epidermal thickness, the formation of collagen fibers, and abnormal keratinocyte proliferation. Importantly, GEN inhibited angiogenesis, the production of angiogenic factors (VEGF-A, Ang-2, TNF-α, and IL-17A), and the proliferation of vascular endothelial cells. Simultaneously, GEN curbed the expression of VEGFR1, VEGFR2, p38, and P-p38 proteins involved in VEGFR signaling. Of note, the suppressive effect of GEN was reversed in the HUVECs with over-expressed VEGFR1 or VEGFR2 related to the cells without transfection. These findings suggest that VEGFR1 and VEGFR2 participate in the anti-angiogenesis of GEN in IMQ-induced psoriasis-like skin lesions in mice.