Novel Findings regarding the Bioactivity of the Natural Blue Pigment Genipin in Human Diseases

Development of new genipin derivatives as potential NASH treatments: Design, synthesis and action mechanism

Nonalcoholic steatohepatitis (NASH) is a multifaceted liver disease. Endoplasmic reticulum stress (ERS), a key driver in NASH pathogenesis, triggers metabolic irregularities, liver steatosis, and inflammation. Genipin, an iridoid from the traditional Chinese medicine Gardenia jasminoides, has demonstrated significant effects against ERS. In the current work, 33 new genipin derivatives were designed and synthesized to evaluate their potential to treat NASH. Notably, G15 emerged as the most potent candidate, significantly attenuating lipid accumulation induced by free fatty acids (FFAs) in L-02 cells. Further investigation revealed that G15's mitigation of ERS was primarily achieved by suppressing the levels of inositol-requiring enzyme 1 (IRE1). Western blot analysis confirmed that G15 effectively down-regulated IRE1 protein expression and decreased the expression levels of its downstream X-box binding protein 1 (XBP1) and signal transducer and activator of transcription 3 (STAT3) proteins, thereby reducing cellular lipid accumulation. In addition, G15 treatment inhibited FFA-induced nitric oxide (NO) production in a concentration-dependent manner and suppressed the secretion of pro-inflammatory cytokines, including IL-1β, IL-6, and TNF-α. Collectively, these findings underscore that G15 has the potential to be a leading candidate for the treatment of NASH by down-regulating the IRE1/XBP1/STAT3 signaling pathway.

Genipa americana L.: A Review on Traditional Uses, Phytochemistry and Biological Activities

Genipa americana L. (Rubiaceae), genip tree, has therapeutic and nutritional potential. This revision aimed to gather information on botanical characteristics, popular uses, phytochemical, and pharmacological aspects of the tree. The methodology adopted integrated literature published between 2000 and 2024, as well as consultations with the World International Intellectual Property Organization (WIPO); resulting in 39 articles and 11 patents to promote this research. The species, which is native and not endemic to Brazil, is most prevalent in the Amazon biome as it is suitable for reconstructing degraded areas, as well as having various traditional applications. Iridoids are the main secondary metabolites present in the species, especially ginipin, geniposide acid, and geniposide, which are the most prevalent in the fruit. The patents registered with the WIPO indicate its use as a colorant, insecticide, anti-inflammatory, and antioxidant potential, in evidence of its antimicrobial and antioxidant activities. Further studies are needed on the mechanisms of the chemical components' action and on ethnopharmacology.

Potential prospects of Chinese medicine application in diabetic retinopathy

Current treatment strategies for diabetic retinopathy (DR), an eye condition that can lead to blindness, have mainly focused on proliferative DR, including vitreous injection, retinal photocoagulation, and vitrectomy. Vitreous injections mainly depend on anti-vascular endothelial growth factor therapy. In this editorial, we comment on the article by Sun et al. We focus specifically on the mechanisms of the protective effect of genipin on the retina. Genipin is a gardenia extract used in traditional Chinese medicine (TCM). In their study, the authors suggest that controlling advanced glycosylation by the intraocular injection of genipin may be a strategy for preventing retinopathy. The innovative use of a Chinese medicine extract injected into the eye to achieve a curative effect has attracted our attention. Although TCM is effective in treating DR, the topical application of DR, especially intraocular injections, is not yet feasible. Herein, we present a brief analysis of effective Chinese medicines for the treatment of DR. The effectiveness of local injections of TCM applied directly into the eyes holds promise as an effective treatment approach for DR.

Advances in the mechanisms of Gardenia jasminoides Ellis in improving diabetes and its complications

Gardenia jasminoides Ellis (Zhi-zi), which belongs to the Rubiaceae family, has been used mainly with its fry fruit for thousands of years, and it is an herb with the homology of medicine and food. In traditional Chinese medicine (TCM) theory, Zhi-zi can be used for "Quench Xiaoke", meaning for therapying diabetes in modern medicine. Based on numerous pharmacological studies, Gardenia jasminoides Ellis (Zhi-zi), and its ingredients, mainly including iridoid glycosides and carotenoids (crocins), possess potent antioxidant and anti-inflammatory properties, and can promote insulin secretion and sensitization, stimulate GLP-1 pathway activity, and protect islet β cells and the macro- and microvascular systems. These properties are the primary reasons why Zhi-zi and its ingredients are effective in reducing glucose levels, treating diabetes, and preventing its complications. This review aims to summarize the current situation and the advances of the studies on the mechanisms of Zhi-zi in improving diabetes and its complications, and it is expected to provide useful and systematic references for future research and clinical application of Zhi-zi and its active ingredients in the therapy of diabetes and complications.

Non-carrier immobilization of yeast cells by genipin crosslinking for the synthesis of prebiotic galactooligosaccharides from plant-derived galactose

Galactooligosaccharides (GOS), as mimics of human milk oligosaccharides, are important prebiotics for modulating the ecological balance of intestinal microbiota. A novel carrier-free cell immobilization method was established using genipin to cross-link Kluyveromyces lactis CGMCC 2.1494, which produced β-galactosidase, an enzyme essential for GOS synthesis. The resulting immobilized cells were characterized as stable by thermogravimetric analysis and confirmed to be crosslinked through scanning electron microscopy analysis (SEM) and Fourier transform infrared spectroscopy (FTIR). The Km and Vmax values of β-galactosidase in immobilized cells towards o-nitrophenyl β-D-galactoside were determined to be 3.446 mM and 2210 μmol min-1 g-1, respectively. The enzyme in the immobilized showed higher thermal and organic solvent tolerance compared to that in free cells. The immobilized cells were subsequently employed for GOS synthesis using plant-derived galactose as the substrate. The synthetic reaction conditions were optimized through both single-factor experiments and response surface methodology, resulting in a high yield of 49.1 %. Moreover, the immobilized cells showed good reusability and could be reused for at least 20 batches of GOS synthesis, with the enzyme activity remaining above 70 % at 35 °C.

Nano-Reactors Based on Ovotransferrin Organic Skeleton through a Ferroptosis-like Strategy Efficiently Enhance Antibacterial Activity

The issue of bacterial resistance is an escalating problem due to the misuse of antibiotics worldwide. This study introduces a new antibacterial mechanism, the ferroptosis-like death (FLD) of bacteria, and an approach to creating green antibacterial nano-reactors. This innovative method leverages natural iron-containing ovotransferrin (OVT) assembled into an organic skeleton to encapsulate low-concentration adriamycin (ADM) for synthesizing eco-friendly nano-reactors. FLD utilizes the Fenton reaction of reactive oxygen species and ferrous ions to continuously produce ·OH, which can attack the bacterial cell membrane and destroy the cell structure to achieve bacteriostasis. The OVT@ADM nano-reactors are nearly spherical, with an average diameter of 247.23 nm and uniform particle sizing. Vitro simulations showed that Fe3+ in OVT@ADM was reduced to Fe2+ by glutathione in the bacterial periplasmic space, which made the structure of OVT loose, leading to a sustained slow release of ADM from OVT@ADM. The H2O2 continuously produced by ADM oxidized Fe2+ through the Fenton reaction to produce ·OH and Fe3+. The results of the antibacterial assay showed that OVT@ADM had a satisfactory antibacterial effect against S. aureus, and the inhibition rate was as high as 99.3%. The cytotoxicity results showed that the mitigation strategy significantly reduced the cytotoxicity caused by ADM. Based on the FLD mechanism, OVT@ADM nano-reactors were evaluated and applied to bacteriostasis. Therefore, the novel antibacterial mechanism and OVT@ADM by the green synthesis method have good application prospects.

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.

Recent advancements in deciphering the therapeutic properties of plant secondary metabolites: phenolics, terpenes, and alkaloids

Plants produce a diverse range of secondary metabolites that serve as defense compounds against a wide range of biotic and abiotic stresses. In addition, their potential curative attributes in addressing various human diseases render them valuable in the development of pharmaceutical drugs. Different secondary metabolites including phenolics, terpenes, and alkaloids have been investigated for their antioxidant and therapeutic potential. A vast number of studies evaluated the specific compounds that possess crucial medicinal properties (such as antioxidative, anti-inflammatory, anticancerous, and antibacterial), their mechanisms of action, and potential applications in pharmacology and medicine. Therefore, an attempt has been made to characterize the secondary metabolites studied in medicinal plants, a brief overview of their biosynthetic pathways and mechanisms of action along with their signaling pathways by which they regulate various oxidative stress-related diseases in humans. Additionally, the biotechnological approaches employed to enhance their production have also been discussed. The outcome of the present review will lead to the development of novel and effective phytomedicines in the treatment of various ailments.

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 β-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.

Comparative Analysis of Phytochemical Profiles and Selected Biological Activities of Various Morphological Parts of Ligustrum vulgare

Ligustrum vulgare (LV), widely cultivated in Europe and often used in hedges, has been historically recognized in folk medicine for its potential health benefits. This study focused on exploring the untargeted identification of secondary metabolites in ethanol extracts (70% v/v) from different morphological parts (young shoots, leaves, flowers and fruits) of LV at various stages of plant development, using ultra-high-performance liquid chromatography with high-resolution mass spectrometry (UHPLC-HRMS). Additionally, the selected biological activities (antioxidant activity, cyclooxygenase-2 inhibition (COX-2), α-amylase inhibition and cytotoxicity) of the tested extracts were determined. Untargeted metabolomics showed that LV extracts were a rich source of phenylethanoid compounds, flavonoids, iridoids and their derivatives. The flowers of LV had the highest content of oleuropein (33.43 ± 2.48 mg/g d.w.). The lowest antioxidant activity was obtained for ripe and post-seasonal fruits, while in the case of other samples, the activity was at a similar level. All tested extracts showed α-amylase and COX-2 inhibitory activity. In addition, LV extracts showed strong antiproliferative properties in colorectal (HT29) and liver (HepG2) cancer cell lines. The obtained results show the difference in the content of bioactive compounds in various morphological parts of Ligustrum vulgare. These differences may influence the multifaceted medicinal potential of this plant.

Gardenia (Gardenia jasminoides Ellis) fruit: a critical review of its functional nutrients, processing methods, health-promoting effects, comprehensive application and future tendencies

Gardenia fruit (GF) is the mature fruit of Gardenia jasminoides Ellis, boasting a rich array of nutrients and phytochemicals. Over time, GF has been extensively utilized in both food and medicinal contexts. In recent years, numerous studies have delved into the chemical constituents of GF and their associated pharmacological activities, encompassing its phytochemical composition and health-promoting properties. This review aims to provide a critical and comprehensive summary of GF research, covering nutrient content, extraction technologies, and potential health benefits, offering new avenues for future investigations and highlighting its potential as an innovative food resource. Additionally, the review proposes novel industrial applications for GF, such as utilizing gardenia yellow/red/blue pigments in the food industry and incorporating it with other herbs in traditional Chinese medicine. By addressing current challenges in developing GF-related products, this work provides insights for potential applications in the cosmetics, food, and health products industries. Notably, there is a need for the development of more efficient extraction methods to harness the nutritional components of GF fully. Further research is needed to understand the specific molecular mechanisms underlying its bioactivities. Exploring advanced processing techniques to create innovative GF-derived products will show great promise for the future.

Synthesis and neuroprotective effects of new genipin derivatives against glutamate-induced oxidative damage

Glutamate-induced oxidative stress is well-known to play a crucial role in the development of neurodegenerative diseases, such as stroke. Genipin, a natural iridoid compound, has demonstrated potential neuroprotective properties but is unstable in physiological conditions. The present study aimed to develop new derivatives of genipin that exhibit improved stability and activity for the treatment of stroke. Nineteen new derivatives were thus designed and synthesized. Their neuroprotective effect against glutamate-induced injury was evaluated in HT22 cells. Among the newly synthesized derivatives, 3e demonstrated significantly greater neuroprotection and improved stability compared to genipin. Specifically, 0.01 μM of 3e was found to effectively attenuate glutamate-induced oxidative damage by inhibiting ROS over-accumulation, reducing MDA content, and restoring the endogenous antioxidative system. Further investigation revealed that 3e inhibited oxidative stress by downregulating the phosphorylation levels of p38 MAPK and activating Nrf2 and HO-1 proteins. These results suggested that 3e has the potential to serve as a promising candidate for the treatment of stroke by protecting against glutamate-induced oxidative stress.

Genipin prevents alpha-synuclein aggregation and toxicity by affecting endocytosis, metabolism and lipid storage

Parkinson's Disease (PD) is a common neurodegenerative disorder affecting millions of people worldwide for which there are only symptomatic therapies. Small molecules able to target key pathological processes in PD have emerged as interesting options for modifying disease progression. We have previously shown that a (poly)phenol-enriched fraction (PEF) of Corema album L. leaf extract modulates central events in PD pathogenesis, namely α-synuclein (αSyn) toxicity, aggregation and clearance. PEF was now subjected to a bio-guided fractionation with the aim of identifying the critical bioactive compound. We identified genipin, an iridoid, which relieves αSyn toxicity and aggregation. Furthermore, genipin promotes metabolic alterations and modulates lipid storage and endocytosis. Importantly, genipin was able to prevent the motor deficits caused by the overexpression of αSyn in a Drosophila melanogaster model of PD. These findings widens the possibility for the exploitation of genipin for PD therapeutics.

Barrier Membranes for Guided Bone Regeneration (GBR): A Focus on Recent Advances in Collagen Membranes

Guided bone regeneration (GBR) has become a clinically standard modality for the treatment of localized jawbone defects. Barrier membranes play an important role in this process by preventing soft tissue invasion outgoing from the mucosa and creating an underlying space to support bone growth. Different membrane types provide different biological mechanisms due to their different origins, preparation methods and structures. Among them, collagen membranes have attracted great interest due to their excellent biological properties and desired bone regeneration results to non-absorbable membranes even without a second surgery for removal. This work provides a comparative summary of common barrier membranes used in GBR, focusing on recent advances in collagen membranes and their biological mechanisms. In conclusion, the review article highlights the biological and regenerative properties of currently available barrier membranes with a particular focus on bioresorbable collagen-based materials. In addition, the advantages and disadvantages of these biomaterials are highlighted, and possible improvements for future material developments are summarized.

Nature's palette: An emerging frontier for coloring dairy products

Consumers all across the world are looking for the most delectable and appealing foods, while also demanding products that are safer, more nutritious, and healthier. Substitution of synthetic colorants with natural colorants has piqued consumer and market interest in recent years. Due to increasing demand, extensive research has been conducted to find natural and safe food additives, such as natural pigments, that may have health benefits. Natural colorants are made up of a variety of pigments, many of which have significant biological potential. Because of the promising health advantages, natural colorants are gaining immense interest in the dairy industry. This review goes over the use of various natural colorants in dairy products which can provide desirable color as well as positive health impacts. The purpose of this review is to provide an in-depth look into the field of food (natural or synthetic) colorants applied in dairy products as well as their potential health benefits, safety, general trends, and future prospects  in food science and technology. In this paper, we listed a plethora of applications of natural colorants in various milk-based products.

Monoterpenes as Sirtuin-1 Activators: Therapeutic Potential in Aging and Related Diseases

Sirtuin 1 (SIRT) is a class III, NAD+-dependent histone deacetylase that also modulates the activity of numerous non-histone proteins through deacylation. SIRT1 plays critical roles in regulating and integrating cellular energy metabolism, response to stress, and circadian rhythm by modulating epigenetic and transcriptional regulation, mitochondrial homeostasis, proteostasis, telomere maintenance, inflammation, and the response to hypoxia. SIRT1 expression and activity decrease with aging, and enhancing its activity extends life span in various organisms, including mammals, and improves many age-related diseases, including cancer, metabolic, cardiovascular, neurodegenerative, respiratory, musculoskeletal, and renal diseases, but the opposite, that is, aggravation of various diseases, such as some cancers and neurodegenerative diseases, has also been reported. Accordingly, many natural and synthetic SIRT1 activators and inhibitors have been developed. Known SIRT1 activators of natural origin are mainly polyphenols. Nonetheless, various classes of non-polyphenolic monoterpenoids have been identified as inducers of SIRT1 expression and/or activity. This narrative review discusses current information on the evidence that supports the role of those compounds as SIRT1 activators and their potential both as tools for research and as pharmaceuticals for therapeutic application in age-related diseases.

Genipin-Crosslinked, Proteosaccharide Scaffolds for Potential Neural Tissue Engineering Applications

Traumatic brain injuries (TBIs) are still a challenge for the field of modern medicine. Many treatment options such as autologous grafts and stem cells show limited promise for the treatment and the reversibility of damage caused by TBIs. Injury beyond the critical size necessitates the implementation of scaffolds that function as surrogate extracellular matrices. Two scaffolds were synthesised utilising polysaccharides, chitosan and hyaluronic acid in conjunction with gelatin. Both scaffolds were chemically crosslinked using a naturally derived crosslinker, Genipin. The polysaccharides increased the mechanical strength of each scaffold, while gelatin provided the bioactive sequence, which promoted cellular interactions. The effect of crosslinking was investigated, and the crosslinked hydrogels showed higher thermal decomposition temperatures, increased resistance to degradation, and pore sizes ranging from 72.789 ± 16.85 µm for the full interpenetrating polymer networks (IPNs) and 84.289 ± 7.658 μm for the semi-IPN. The scaffolds were loaded with Dexamethasone-21-phosphate to investigate their efficacy as a drug delivery vehicle, and the full IPN showed a 100% release in 10 days, while the semi-IPN showed a burst release in 6 h. Both scaffolds stimulated the proliferation of rat pheochromocytoma (PC12) and human glioblastoma multiforme (A172) cell cultures and also provided signals for A172 cell migration. Both scaffolds can be used as potential drug delivery vehicles and as artificial extracellular matrices for potential neural regeneration.