Genipin inhibits the inflammatory response of rat brain microglial cells

Mechanism of Tianma-Gouteng granules lowering blood pressure based on the bile acid-regulated Farnesoid X Receptor-Fibroblast Growth Factor 15- Cholesterol 7α-hydroxylase pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Tianma-Gouteng granules (TGG) is a traditional Chinese medicine (TCM) compound that was first recorded by modern medical practitioner Hu Guangci in "New Meaning of the Treatment of Miscellaneous Diseases in Traditional Chinese Medicine". It is widely used to treat hypertensive vertigo, headache and insomnia.

AIM OF STUDY

To investigate the antihypertensive effect of TGG and explore its mechanism.

MATERIALS AND METHODS

Spontaneously hypertensive rats (SHR) were prepared a model of the ascendant hyperactivity of liver yang syndrome (AHLYS), blood pressure and general state of rats were recorded. A series of experiments were performed by enzyme-linked immunosorbent assay (ELISA), ultra high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS), 16S rRNA sequencing, real-time fluorescence quantitative PCR (RT-qPCR), and enzymatic colorimetry.

RESULTS

TGG can effectively lower blood pressure and improve related symptoms. TGG significantly reduced the levels of IL-1β, IL-6, TNF-α, Renin and AngII. A total of 17 differential metabolites were found in plasma, with the two most potent metabolic pathways being glycerophospholipid metabolism and primary bile acid biosynthesis. After TGG intervention, 7 metabolite levels decreased and 10 metabolite levels increased. TGG significantly increased the relative abundance of Desulfovibio, Lachnoclostridium, Turicibacter, and decreased the relative abundance of Alluobaculum and Monoglobu. TGG also downregulated Farnesoid X Receptor (FXR) and Fibroblast Growth Factor 15 (FGF15) levels in the liver and ileum, upregulated Cholesterol 7α-hydroxylase (CYP7A1) levels, and regulated total bile acid (TBA) levels.

CONCLUSION

TGG can regulate bile acid metabolism through liver-gut axis, interfere with related intestinal flora and plasma metabolites, decrease blood pressure, and positively influence the pathologic process of SHR with AHLYS. When translating animal microbiota findings to humans, validation studies are essential to confirm reliability and applicability, particularly through empirical human research.

AP39, a novel mitochondria-targeted hydrogen sulfide donor ameliorates doxorubicin-induced cardiotoxicity by regulating the AMPK/UCP2 pathway

Doxorubicin (DOX) is a broad-spectrum, highly effective antitumor agent; however, its cardiotoxicity has greatly limited its use. Hydrogen sulfide (H2S) is an endogenous gaseous transmitter that exerts cardioprotective effects via the regulation of oxidative stress and apoptosis and maintenance of mitochondrial function, among other mechanisms. AP39 is a novel mitochondria-targeted H2S donor that, at appropriate concentrations, attenuates intracellular oxidative stress damage, maintains mitochondrial function, and ameliorates cardiomyocyte injury. In this study, DOX-induced cardiotoxicity models were established using H9c2 cells and Sprague-Dawley rats to evaluate the protective effect of AP39 and its mechanisms of action. Both in vivo and in vitro experiments showed that DOX induces oxidative stress injury, apoptosis, and mitochondrial damage in cardiomyocytes and decreases the expression of p-AMPK/AMPK and UCP2. All DOX-induced changes were attenuated by AP39 treatment. Furthermore, the protective effect of AP39 was significantly attenuated by the inhibition of AMPK and UCP2. The results suggest that AP39 ameliorates DOX-induced cardiotoxicity by regulating the expression of AMPK/UCP2.

Investigation of Liquid Collagen Ink for Three-Dimensional Printing

Three-dimensional printing provides more versatility in the fabrication of scaffold materials for hard and soft tissue replacement, but a critical component is the ink. The ink solution should be biocompatible, stable, and able to maintain scaffold shape, size, and function once printed. This paper describes the development of a collagen ink that remains in a liquid pre-fibrillized state prior to printing. The liquid stability occurs due to the incorporation of ethylenediaminetetraacetic acid (EDTA) during dialysis of the collagen. Collagen inks were 3D-printed using two different printers. The resulting scaffolds were further processed using two different chemical crosslinkers, 1-Ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride)/N-hydroxysuccinimide (EDC/NHS) and genipin; gold nanoparticles were conjugated to the scaffolds. The 3D-printed scaffolds were characterized to determine their extrudability, stability, amount of AuNP conjugated, and overall biocompatibility via cell culture studies using fibroblast cells and stroma cells. The results demonstrated that the liquid collagen ink was amendable to 3D printing and was able to maintain its 3D shape. The scaffolds could be conjugated with gold nanoparticles and demonstrated enhanced biocompatibility. It was concluded that the liquid collagen ink is a good candidate material for the 3D printing of tissue scaffolds.

Genipin and pyrogallol: Two natural small molecules targeting the modulation of disordered proteins in Alzheimer's disease

Alzheimer's disease (AD) is characterized by the aggregation of disordered proteins, such as amyloid beta (Aβ) and tau, leading to neurotoxicity and disease progression. Despite numerous efforts, effective inhibitors of Aβ and tau aggregates have not been developed. Thus, we aimed to screen natural small molecules from crude extracts that target various pathologies and are prescribed for patients with neurological diseases. In this study, we screened 162 natural small molecules prescribed for neurological diseases and identified genipin and pyrogallol as hit compounds capable of simultaneously regulating the aggregation of Aβ and tau K18. Moreover, we confirmed the dual modulatory effects of these compounds on the reduction of amyloid-mediated neurotoxicity in vitro and the disassembly of preformed Aβ42 and tau K18 fibrils. Furthermore, we observed the alleviatory effects of genipin and pyrogallol against AD-related pathologies in triple transgenic AD mice. Molecular dynamics and docking simulations revealed the molecular interaction dynamics of genipin and pyrogallol with Aβ42 and tau K18, providing insights into their suppression of aggregation. Our findings suggest the therapeutic potential of genipin and pyrogallol as dual modulators for the treatment of AD by inhibiting aggregation or promoting dissociation of Aβ and tau.

Improved Physiochemical Properties of Chitosan@PCL Nerve Conduits by Natural Molecule Crosslinking

Nerve conduits may represent a valuable alternative to autograft for the regeneration of long-gap damages. However, no NCs have currently reached market approval for the regeneration of limiting gap lesions, which still represents the very bottleneck of this technology. In recent years, a strong effort has been made to envision an engineered graft to tackle this issue. In our recent work, we presented a novel design of porous/3D-printed chitosan/poly-ε-caprolactone conduits, coupling freeze drying and additive manufacturing technologies to yield conduits with good structural properties. In this work, we studied genipin crosslinking as strategy to improve the physiochemical properties of our conduit. Genipin is a natural molecule with very low toxicity that has been used to crosslink chitosan porous matrix by binding the primary amino group of chitosan chains. Our characterization evidenced a stabilizing effect of genipin crosslinking towards the chitosan matrix, with reported modified porosity and ameliorated mechanical properties. Given the reported results, this method has the potential to improve the performance of our conduits for the regeneration of long-gap nerve injuries.

Changes in RBM47 expression based on the timing of melatonin administration and its effects on Nrf2 activity in the hippocampus

Melatonin is an endogenous indoleamine that plays a significant role in various physiological processes, including the sleep-wake cycle, anxiety, immunity, and circadian rhythms. However, it is important to clarify that melatonin does not directly control circadian rhythms. Circadian rhythms are primarily synchronized by light, which acts on the suprachiasmatic nucleus (SCN) and subsequently regulates melatonin production. This light-mediated synchronization of circadian rhythms is essential for maintaining the alignment of the body with the light-dark cycle. In this study, we investigated the efficacy of melatonin administration during different times of the day or night and explored its neuroprotective effects. Furthermore, we aimed to apply these findings to rodent models of dementia, aging, and neuro-inflammation for potential therapeutic applications. Our study uncovered novel evidence suggesting the involvement of RNA-binding motif protein (RBM)-47 and Nrf2 in the signaling pathways associated with melatonin administration during both day and night. We examined the role of RBM47 in Nrf2 activity through siRNA or CRISPR-mediated knockdown experiments using hippocampal neuronal cells and lentivirus injections in mice. In 5xFAD/aging/neuroinflammatory mouse models, antioxidant effects were enhanced when melatonin was administered during the day compared to nighttime administration. Furthermore, mRNA analysis and molecular biology experiments revealed the differential expression of RBM47 depending on the timing of melatonin administration. These findings suggest that a decrease in RBM47 expression may improve the antioxidant defense system in the hippocampus. Consequently, administering melatonin during the day rather than at night may present a plausible therapeutic strategy as an antioxidant.

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.

A Pilot Study to Evaluate Genipin in Staphylococcus aureus and Pseudomonas aeruginosa Keratitis Models: Modulation of Pro-Inflammatory Cytokines and Matrix Metalloproteinases

Infectious keratitis is a vision-threatening microbial infection. The increasing antimicrobial resistance and the fact that severe cases often evolve into corneal perforation necessitate the development of alternative therapeutics for effective medical management. Genipin, a natural crosslinker, was recently shown to exert antimicrobial effects in an ex vivo model of microbial keratitis, highlighting its potential to serve as a novel treatment for infectious keratitis. This study aimed to evaluate the antimicrobial and anti-inflammatory effects of genipin in an in vivo model of Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa) keratitis. Clinical scores, confocal microscopy, plate count, and histology were carried out to evaluate the severity of keratitis. To assess the effect of genipin on inflammation, the gene expression of pro- and anti-inflammatory factors, including matrix metalloproteinases (MMPs), were evaluated. Genipin treatment alleviated the severity of bacterial keratitis by reducing bacterial load and repressing neutrophil infiltration. The expression of interleukin 1B (IL1B), interleukin 6 (IL6), interleukin 8 (IL8), interleukin 15 (IL15), tumor necrosis factor-α (TNF-α), and interferon γ (IFNγ), as well as MMP2 and MMP9, were significantly reduced in genipin-treated corneas. Genipin promoted corneal proteolysis and host resistance to S. aureus and P. aeruginosa infection by suppressing inflammatory cell infiltration, regulating inflammatory mediators, and downregulating the expression of MMP2 and MMP9.

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.

Identification of Genipin as a Potential Treatment for Type 2 Diabetes

The prevalence of type 2 diabetes (T2D) has been rising dramatically in many countries around the world. The main signatures of T2D are insulin resistance and dysfunction of β-cells. While there are several pharmaceutical therapies for T2D, no effective treatment is available for reversing the functional decline of pancreatic β-cells in T2D patients. It has been well recognized that glucagon-like peptide-1 (GLP-1), which is an incretin hormone secreted from intestinal L-cells, plays a vital role in regulating glycemic homeostasis via potentiating glucose-stimulated insulin secretion and promoting β-cell function. We found that genipin, a natural compound from Elli, can directly target intestinal L-cells, leading to the secretion of GLP-1. Incubation of the cells with genipin elicited a rapid increase in intracellular Ca²⁺. Inhibition of PLC ablated genipin-stimulated Ca²⁺ increase and GLP-1 secretion, suggesting that genipin-induced GLP-1 release from cells is dependent on the PLC/Ca²⁺ pathway. In vivo, acute administration of genipin stimulated GLP-1 secretion in mice. Chronically, treatment with genipin via oral gavage at 50 mg/kg/day for 6 weeks reversed hyperglycemia and insulin resistance in high-fat-diet (HFD)-induced obese mice. Moreover, genipin alleviated the impaired lipid metabolism and decreased lipid accumulation in the liver of obese mice. These results suggest that naturally occurring genipin might potentially be a novel agent for the treatment of T2D and diet-induced fatty liver disease.

Neurological disorders of COVID-19: insights to applications of natural products from plants and microorganisms

In addition to the typical respiratory manifestations, various disorders including involvement of the nerve system have been detected in COVID-19 ranging from 22 to 36%. Although growing records are focusing on neurological aspects of COVID-19, the pathophysiological mechanisms and related therapeutic methods remain obscure. Considering the increased concerns of SARS-CoV-2 potential for more serious neuroinvasion conditions, the present review attempts to focus on the neuroprotective effects of natural compounds as the principle source of therapeutics inhibiting multiple steps of the SARS-CoV-2 infection cycle. The great majority of the natural products with anti-SARS-CoV-2 activity mainly inhibit the attachment, entry and gene expression rather than the replication, assembly, or release. Although microbial-derived natural products comprise 38.5% of the known natural products with neuroprotective effects following viral infection, the neuroprotective potential of the majority of microorganisms is still undiscovered. Among natural products, chrysin, huperzine A, ginsenoside Rg1, pterostilbene, and terrein have shown potent in vitro neuroprotective activity and can be promising for new or repurpose drugs for neurological complications of SARS-CoV-2.

Investigation of the synergistic effect of platelet-rich plasma and polychromatic light on human dermal fibroblasts seeded chitosan/gelatin scaffolds for wound healing

Conventional wound healing treatments are insufficient for chronic wounds caused by factors such as senescence of fibroblasts, reduced growth factor synthesis, and poor angiogenesis. Recently, tissue engineering approaches have been investigated to develop effective therapies. In this study, a biochemical/biophysical stimulant-based 3D system was developed for the healing of chronic wounds. In this direction, genipin crosslinked chitosan (CHT)/gelatin (GEL) scaffolds were fabricated by freeze-drying and loaded with platelet-rich plasma (PRP). The scaffolds were seeded with human dermal fibroblasts and then, polychromatic light in near infrared region (NIR) was applied to the scaffolds for activating the platelets and stimulating the fibroblasts (photoactivation, PAC). Thus, fibroblasts were stimulated both chemically and physically by PRP and light, respectively. Cell migration, proliferation, morphology, gene expressions and reactive oxygen species (ROS) activity were evaluated in-vitro. Laminin and collagen 4 expressions that are important for extracellular matrix (ECM) formation, and PDGF (Platelet-derived growth factor) and VEGF (Vascular endothelial growth factor) expressions that are important for vascularization significantly increased in the presence of both PRP and light. Besides, PRP and light improved cell migration in 3D core-and shell model synergistically. Hydrogen peroxide content decreased in both PRP and light, indicating inhibition of ROS production. It was concluded that the stimulation of platelets with light in the NIR has a great potential to use for both platelets activation and stimulation of fibroblasts. As a result, an effective therapy can be developed for chronic wounds by using scaffold-based 3D systems together with PRP and photostimulation.

Neuroprotective Effects of Exogenous Irisin in Kainic Acid-Induced Status Epilepticus

Elevated reactive oxygen species (ROS) level is considered a crucial causative factor for neuronal damage in epilepsy. Irisin has been reported to ameliorate mitochondrial dysfunction and to reduce ROS levels; therefore, in this study, the effect of exogenous irisin on neuronal injury was evaluated in rats with kainic acid (KA)-induced status epilepticus (SE). Our results showed that exogenous irisin treatment significantly increased the expression of brain-derived neurotrophic factor (BDNF) and uncoupling protein 2 (UCP2), and reduced the levels of neuronal injury and mitochondrial oxidative stress. Additionally, an inhibitor of UCP2 (genipin) was administered to investigate the underlying mechanism of irisin-induced neuroprotection; in rats treated with genipin, the neuroprotective effects of irisin on KA-induced SE were found to be partially reversed. Our findings confirmed the neuroprotective effects of exogenous irisin and provide evidence that these effects may be mediated via the BDNF/UCP2 pathway, thus providing valuable insights that may aid the development of exogenous irisin treatment as a potential therapeutic strategy against neuronal injury in epilepsy.

Genipin in an Ex Vivo Corneal Model of Bacterial and Fungal Keratitis

Purpose

To determine whether genipin (a natural crosslinker) could reduce the colonization and proliferation of bacteria and fungi in an ex vivo model of corneal infection.

Methods

This study, using an ex vivo model of bacterial and fungal keratitis, investigated the antimicrobial efficacy of genipin crosslinking. Excised corneoscleral buttons were wounded by scalpel incision and subsequently infected with Staphylococcus aureus, Pseudomonas aeruginosa, or Candida albicans. After inoculation, corneas were treated with genipin for 24 hours at 37°C. Histologic examinations were carried out, and the number of viable colony-forming units (CFU)/cornea was determined.

Results

Genipin exerts bactericidal action against S. aureus and P. aeruginosa, as well as fungicidal action against C. albicans and significantly reduced the CFU compared to contralateral eyes that received saline treatment (P < 0.05).

Conclusions

These data identify genipin as a novel ocular antimicrobial agent that has the potential to be incorporated into the therapeutic armamentarium against microbial keratitis.

Translational Relevance

This study provided evidence for the antimicrobial and antifungal properties of genipin as an alternative crosslinker that could be used in the management of infectious keratitis.

Activity of Selected Group of Monoterpenes in Alzheimer's Disease Symptoms in Experimental Model Studies-A Non-Systematic Review

Alzheimer's disease (AD) is the leading cause of dementia and cognitive function impairment. The multi-faced character of AD requires new drug solutions based on substances that incorporate a wide range of activities. Antioxidants, AChE/BChE inhibitors, BACE1, or anti-amyloid platelet aggregation substances are most desirable because they improve cognition with minimal side effects. Plant secondary metabolites, used in traditional medicine and pharmacy, are promising. Among these are the monoterpenes-low-molecular compounds with anti-inflammatory, antioxidant, enzyme inhibitory, analgesic, sedative, as well as other biological properties. The presented review focuses on the pathophysiology of AD and a selected group of anti-neurodegenerative monoterpenes and monoterpenoids for which possible mechanisms of action have been explained. The main body of the article focuses on monoterpenes that have shown improved memory and learning, anxiolytic and sleep-regulating effects as determined by in vitro and in silico tests-followed by validation in in vivo models.

Natural Terpenoids as Neuroinflammatory Inhibitors in LPS-stimulated BV-2 Microglia

Neuroinflammation is a typical feature of many neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease. Microglia, the resident immune cells of the brain, readily become activated in response to an infection or an injury. Uncontrolled and overactivated microglia can release pro-inflammatory and cytotoxic factors and are the major culprits in neuroinflammation. Hence, research on novel neuroinflammatory inhibitors is of paramount importance for the treatment of neurodegenerative diseases. Bacterial lipopolysaccharide, widely used in the studies of brain inflammation, initiates several major cellular activities that critically contribute to the pathogenesis of neuroinflammation. This review will highlight the progress on terpenoids, an important and structurally diverse group of natural compounds, as neuroinflammatory inhibitors in lipopolysaccharidestimulated BV-2 microglial cells over the last 20 years.

Polydatin inhibits LPS-induced inflammatory response in BV2 microglia by disrupting the formation of lipid rafts

OBJECTIVE

Polydatin has been used in the treatment of various inflammatory diseases. However, its role in the regulation of neuroinflammation has not been reported. In this study, we designed to investigate the anti-inflammatory effects of polydatin in LPS-stimulated BV2 microglia cells.

METHODS

Inflammatory mediators TNF-α, IL-1β, NO, and PGE2 production were measured by ELISA. The protein of signaling pathways were detected by western blot analysis.

RESULTS

The results showed that polydatin significantly ameliorated the production of TNF-α, IL-1β, NO, and PGE2 up-regulated by LPS. Polydatin also blocked LPS-induced NF-κB activation. In addition, PI3K and AKT, the up-stream molecules of NF-κB signaling pathway, were inhibited by the treatment of polydatin. Also, we found the formation of lipid rafts was inhibited by polydatin through attenuating the cholesterol content. Finally, polydatin was found to increase the expression of ABCA1 and ABCG1.

CONCLUSION

In conclusion, the results of the present study suggested that polydatin exhibited its anti-inflammatory effects in BV2 cells through disrupting lipid rafts, which subsequently inhibiting PI3K/AKT signaling pathway.

Genipin improves reproductive health problems caused by circadian disruption in male mice

BACKGROUND

Circadian rhythm disruption impacts a wide range of physiological processes, including fertility. However, the effect of circadian disruption on male spermatogenesis and fertility, and treatments for these effects have been largely unexplored at the molecular level.

METHODS

In this study, we examined the effects of genipin on improving the reproductive health problems caused by circadian disruption. Three groups of animals were fed under different conditions: control group (normal T cycle with saline), group of shortened T cycles (Light/Dark = 4 hours/4 hours) with saline, and a group of shortened T cycles with genipin by oral gavage. The male fertility was evaluated by fertility study and pups parameters analysis after successful sexual behavior and mating with female mice. We sacrificed the treated animals after 5 or 10 weeks and collected the testis, sperm and serum for histological analysis, sperm motility assay, and serum hormone detection, respectively. Furthermore, the effect of genipin was assessed by detection of progesterone secretion and steroidogenic key proteins expression, including StAR and CYP11A1, in mouse Leydig tumor MLTC-1 cells.

RESULTS

Male mice exposed to shortened light-dark cycles, much shorter than 24 hours, had reduced fertility with decreased sperm concentrations and sperm motility. Male mice under circadian disruption have reduced testis size and abnormal morphology, leading to lower fertility rates, reduced litter size and pup body weight. Treatment with exogenous genipin, a natural plant-derived compound, alleviated circadian disruption-induced damage to fertility and spermatogenesis and normalized testosterone, dihydrotestosterone (DHT), and androstenedione (ASD) levels in the male mice. The levels of key proteins involved in steroidogenesis, StAR and CYP11A1, were reduced in mouse testes after the circadian disruption, but genipin treatment restored the reduction. The mRNA expression of SRD5A1, which encodes an androgen synthesis enzyme, was also upregulated by genipin treatment. Furthermore, genipin treatment showed a positive effect on steroidogenesis in MLTC-1 cells, resulting in an increase in hormone secretion and the upregulation of StAR and CYP11A1.

CONCLUSIONS

Our results showed an association between circadian disruption and reproductive health problems in male mice and indicated that treatments with genipin have positive effects on the reproductive health of male mice with circadian rhythm disorders.

Hybrids of aurantiamide acetate and isopropylated genipin as potential anti-inflammatory agents: The design, synthesis, and biological evaluation

A novel series of hybrids designed on the basis of aurantiamide acetate and isopropylated genipin were synthesized and biologically evaluated as anti-inflammatory agents. Among them, compound 7o exhibited the best inhibitory activity against TNF-α secretion (IC₅₀  = 16.90 μM) and was selected for further in vitro and in vivo functional study. The results demonstrated that 7o was capable of suppressing the expression of LPS-induced iNOS and COX-2, as well as reducing the production of NO at the concentration of 5 μM, which may be resulted from its regulation of NF-κB signaling and MAPK signaling. Moreover, compound 7o exhibited favorable in vivo anti-inflammatory activity with an inhibition rate of 53.32% against xylene-induced ear swelling in mice at the dose of 5 mg/kg.

Neuroinflammation in Alzheimer's Disease: Microglia, Molecular Participants and Therapeutic Choices

Alzheimer's disease is the world's most common dementing illness. It is pathologically characterized by β-amyloid accumulation, extracellular senile plaques and intracellular neurofibrillary tangles formation, and neuronal necrosis and apoptosis. Neuroinflammation has been widely recognized as a crucial process that participates in AD pathogenesis. In this review, we briefly summarized the involvement of microglia in the neuroinflammatory process of Alzheimer's disease. Its roles in the AD onset and progression are also discussed. Numerous molecules, including interleukins, tumor necrosis factor alpha, chemokines, inflammasomes, participate in the complex process of AD-related neuroinflammation and they are selectively discussed in this review. In the end of this paper from an inflammation- related perspective, we discussed some potential therapeutic choices.

Genipin inhibits rotavirus-induced diarrhea by suppressing viral replication and regulating inflammatory responses

Rotavirus is the leading cause of acute gastroenteritis among young children worldwide. However, agents specifically designed to treat rotavirus infection have not been developed yet. In this study, the anti-rotavirus and anti-inflammatory effects of genipin, a chemical compound found in the fruit of Gardenia jasminoides, were evaluated. Genipin had an antiviral effect against the human rotavirus Wa and SA-11 strains in vitro, and it inhibited two distinct stages of the viral replication cycle: attachment and penetration (early stage) in pre-treatment and assembly and release (late stage) in post-treatment. Additionally, genipin downregulated nitric oxide synthase and pro-inflammatory cytokines in lipopolysaccharide-stimulated RAW264.7 cells and rotavirus-infected Caco-2 cells. Oral administration of genipin before and after viral infection with the murine rotavirus epidemic diarrhea of infant mice strain led to a reduced duration of diarrhea and faecal viral shedding and to decreased destruction of the enteric epithelium. Genipin could have potential as a natural compound with preventive and therapeutic effects against infection and colitis caused by rotavirus.

Synthesis and biological evaluation of geniposide derivatives as potent and selective PTPlB inhibitors

Herein a series of Geniposide derivatives were designed, synthesized and evaluated as protein tyrosine phosphatase 1B (PTPlB) inhibitors. Most of these compounds exhibited potent in vitro PTP1B inhibitory activities, the representative 7a and 17f were found to be the most potent inhibitors against the enzyme with IC₅₀ values of 0.35 and 0.41 μM, respectively. More importantly, they showcased 4 to10-fold selectivity over SHP2 and 3-fold over TCPTP. Further biological activity studies revealed that compounds 7a, 17b and 17f could effectively enhance insulin-stimulated glucose uptake with no significant cytotoxicity. Subsequent molecular docking and structural activity relationship analyses demonstrated that the glucose scaffold, benzylated glycosyl groups, and arylethenesulfonic acid ester significantly impact on the activity and selectivity.

Gardenia jasminoides extract and its constituent, genipin, inhibit activation of CD3/CD28 co-stimulated CD4+ T cells via ORAI1 channel

Gardenia jasminoides (GJ) is a widely used herbal medicine with anti-inflammatory properties, but its effects on the ORAI1 channel, which is important in generating intracellular calcium signaling for T cell activation, remain unknown. In this study, we investigated whether 70% ethanolic GJ extract (GJ_EtOH) and its subsequent fractions inhibit ORAI1 and determined which constituents contributed to this effect. Whole-cell patch clamp analysis revealed that GJ_EtOH (64.7% ± 3.83% inhibition at 0.1 mg/ml) and all its fractions showed inhibitory effects on the ORAI1 channel. Among the GJ fractions, the hexane fraction (GJ_HEX, 66.8% ± 9.95% at 0.1 mg/ml) had the most potent inhibitory effects in hORAI1-hSTIM1 co-transfected HEK293T cells. Chemical constituent analysis revealed that the strong ORAI1 inhibitory effect of GJ_HEX was due to linoleic acid, and in other fractions, we found that genipin inhibited ORAI1. Genipin significantly inhibited I_ORAI1 and interleukin-2 production in CD3/CD28-stimulated Jurkat T lymphocytes by 35.9% ± 3.02% and 54.7% ± 1.32% at 30 μM, respectively. Furthermore, the same genipin concentration inhibited the proliferation of human primary CD4⁺ T lymphocytes stimulated with CD3/CD28 antibodies by 54.9% ± 8.22%, as evaluated by carboxyfluorescein succinimidyl ester assay. Our findings suggest that genipin may be one of the active components of GJ responsible for T cell suppression, which is partially mediated by activation of the ORAI1 channel. This study helps us understand the mechanisms of GJ in the treatment of inflammatory diseases.

Genipin cross-linked carbon dots for antimicrobial, bioimaging and bacterial discrimination

Multifunctional carbon dots (CDs) present enormous potential in numerous applications and have attracted widespread attention for various applications in the biomedical field. Bacterial infection is a common health issue; the development of antibacterial materials with low toxicity and good biocompatibility is becoming more important. In this work, we synthesized a new type of nitrogen co-doped carbon dots-genipin covalent conjugate (N-CDs-GP) via hydrothermal methods. The microstructure and chemical composition of the N-CDs-GP were characterized. The biocompatibility, stability, antibacterial activity, and fluorescence performance of the N-CDs-GP were assessed. The results revealed that N-CDs-GP possessed high biocompatibility, high light stability, and broad antibacterial activity. Additionally, selective Gram-positive bacterial imaging by N-CDs-GP provided a more rapid method of bacterial detection. The N-CDs-GP have the potential to be applied as bioimaging and antibacterial agents and for bacterial discrimination.

Inhibitory Effects of Myricetin on Lipopolysaccharide-Induced Neuroinflammation

Microglial activation elicits an immune response by producing proinflammatory modulators and cytokines that cause neurodegeneration. Therefore, a plausible strategy to prevent neurodegeneration is to inhibit neuroinflammation caused by microglial activation. Myricetin, a natural flavanol, induces neuroprotective effects by inhibiting inflammation and oxidative stress. However, whether myricetin inhibits lipopolysaccharide (LPS)-induced neuroinflammation in hippocampus and cortex regions is not known. To test this, we examined the effects of myricetin on LPS-induced neuroinflammation in a microglial BV2 cell line. We found that myricetin significantly downregulated several markers of the neuroinflammatory response in LPS-induced activated microglia, including inducible nitric oxide (NO) synthase (iNOS), cyclooxygenase-2 (COX-2), and proinflammatory modulators and cytokines such as prostaglandin E2 (PGE₂), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α). Moreover, myricetin suppressed the expression of c-Jun NH2-terminal kinase (JNK), p38 MAPK, and extracellular signal-regulated kinase (ERK), which are components of the mitogen-activated protein kinase (MAPK) signaling pathway. Furthermore, myricetin inhibited LPS-induced macrophages and microglial activation in the hippocampus and cortex of mice. Based on our results, we suggest that myricetin inhibits neuroinflammation in BV2 microglia by inhibiting the MAPK signaling pathway and the production of proinflammatory modulators and cytokines. Therefore, this could potentially be used for the treatment of neuroinflammatory diseases.

Genipin increases oxaliplatin-induced cell death through autophagy in gastric cancer

Oxaliplatin is used for treatment in combination with many drugs. However, the survival rate is still low due to side effects and drug resistance. Therefore, the combination with natural products was required for increasing efficacy and reducing side effects. Genipin, a natural product derived from the Gardenia jasminoides, associated with anti-angiogenic, anti-proliferative, hypertension, inflammatory, and the Hedgehog pathway. It is not known that genipin increases the therapeutic effect of oxaliplatin in gastric cancer. In this study, we found that genipin sensitizes oxaliplatin-induced apoptosis for the first time using colony forming assay, FACS analysis, and western blotting in gastric cancer. Additionally, genipin induced p53 expression in AGS, MKN45, and MKN28 cells. Also, genipin induced autophagy and LC3 expression. Knockdown of LC3 decreased cell death enhanced by the combination of oxaliplatin and genipin. In summary, we showed that genipin increases the oxaliplatin-induced cell death via p53-DRAM autophagy. Based on this, we suggest that genipin is a sensitizer of oxaliplatin.

Huang-Lian Jie-Du decoction: a review on phytochemical, pharmacological and pharmacokinetic investigations

Huang-Lian Jie-Du decoction (HLJDD), a famous traditional Chinese prescription constituted by Rhizoma Coptidis, Radix Scutellariae, Cortex Phellodendri and Fructus Gradeniae, has notable characteristics of dissipating heat and detoxification, interfering with tumors, hepatic diseases, metabolic disorders, inflammatory or allergic processes, cerebral diseases and microbial infections. Based on the wide clinical applications, accumulating investigations about HLJDD focused on several aspects: (1) chemical analysis to explore the underlying substrates responsible for the therapeutic effects; (2) further determination of pharmacological actions and the possible mechanisms of the whole prescription and of those representative ingredients to provide scientific evidence for traditional clinical applications and to demonstrate the intriguing molecular targets for specific pathological processes; (3) pharmacokinetic feature studies of single or all components of HLJDD to reveal the chemical basis and synergistic actions contributing to the pharmacological and clinically therapeutic effects. In this review, we summarized the main achievements of phytochemical, pharmacological and pharmacokinetic profiles of HLJDD and its herbal or pharmacologically active chemicals, as well as our understanding which further reveals the significance of HLJDD clinically.

Molecular Mechanisms Responsible for Pharmacological Effects of Genipin on Mitochondrial Proteins

Genipin, a natural compound from Gardenia jasminoides, is a well-known compound in Chinese medicine that is used for the treatment of cancer, inflammation, and diabetes. The use of genipin in classical medicine is hindered because of its unknown molecular mechanisms of action apart from its strong cross-linking ability. Genipin is increasingly applied as a specific inhibitor of proton transport mediated by mitochondrial uncoupling protein 2 (UCP2). However, its specificity for UCP2 is questionable, and the underlying mechanism behind its action is unknown. Here, we investigated the effect of genipin in different systems, including neuroblastoma cells, isolated mitochondria, isolated mitochondrial proteins, and planar lipid bilayer membranes reconstituted with recombinant proteins. We revealed that genipin activated dicarboxylate carrier and decreased the activity of UCP1, UCP3, and complex III of the respiratory chain alongside with UCP2 inhibition. Based on competitive inhibition experiments, the use of amino acid blockers, and site-directed mutagenesis of UCP1, we propose a mechanism of genipin’s action on UCPs. At low concentrations, genipin binds to arginine residues located in the UCP funnel, which leads to a decrease in UCP’s proton transporting function in the presence of long chain fatty acids. At concentrations above 200 μM, the inhibitory action of genipin on UCPs is overlaid by increased nonspecific membrane conductance due to the formation of protein-genipin aggregates. Understanding the concentration-dependent mechanism of genipin action in cells will allow its targeted application as a drug in the above-mentioned diseases.

Cicadidae Periostracum, the Cast-Off Skin of Cicada, Protects Dopaminergic Neurons in a Model of Parkinson's Disease

Parkinson's disease (PD) is characterized by dopaminergic neuronal loss in the substantia nigra pars compacta (SNPC) and the striatum. Nuclear receptor-related 1 protein (Nurr1) is a nuclear hormone receptor implicated in limiting mitochondrial dysfunction, apoptosis, and inflammation in the central nervous system and protecting dopaminergic neurons and a promising therapeutic target for PD. Cicadidae Periostracum (CP), the cast-off skin of Cryptotympana pustulata Fabricius, has been used in traditional medicine for its many clinical pharmacological effects, including the treatment of psychological symptoms in PD. However, scientific evidence for the use of CP in neurodegenerative diseases, including PD, is lacking. Here, we investigated the protective effects of CP on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine- (MPTP-) induced PD in mice and explored the underlying mechanisms of action, focusing on Nurr1. CP increased the expression levels of Nurr1, tyrosine hydroxylase, DOPA decarboxylase, dopamine transporter, and vesicular monoamine transporter 2 via extracellular signal-regulated kinase phosphorylation in differentiated PC12 cells and the mouse SNPC. In MPTP-induced PD, CP promoted recovery from movement impairments. CP prevented dopamine depletion and protected against dopaminergic neuronal degradation via mitochondria-mediated apoptotic proteins such as B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X, cytochrome c, and cleaved caspase-9 and caspase-3 by inhibiting MPTP-induced neuroinflammatory cytokines, inducible nitric oxide synthase, cyclooxygenase 2, and glial/microglial activation. Moreover, CP inhibited lipopolysaccharide-induced neuroinflammatory cytokines and response levels and glial/microglial activation in BV2 microglia and the mouse brain. Our findings suggest that CP might contribute to neuroprotective signaling by regulating neurotrophic factors primarily via Nurr1 signaling, neuroinflammation, and mitochondria-mediated apoptosis.

7-Deoxy-trans-dihydronarciclasine Isolated from Lycoris chejuensis Inhibits Neuroinflammation in Experimental Models

Overactivated microglia and persistent neuroinflammation hold an important role in the pathophysiology of neurodegenerative diseases. The extract of Lycoris chejuensis (CJ) and its active compound, 7-deoxy-trans-dihydronarciclasine (named E144), attenuated expressions of pro-inflammatory factors, including nitric oxide, prostaglandin E₂, inducible nitric oxide synthase, cyclooxygenase-2 (COX-2), tumor necrosis factor α (TNF-α), and interleukin 6, secreted by lipopolysaccharide-activated BV-2 microglial cells, as measured by an enzyme-linked immunosorbent assay or western blotting. In contrast, CJ extract and E144 promoted the secretion of the anti-inflammatory cytokine, interleukin 10. Moreover, we found that E144 attenuated the expression of TNF-α and COX-2 in the cerebral cortex of lipopolysaccharide-treated mice and/or T2576 transgenic mice as well as reduced the reactive immune cells visualized by ionized calcium-binding adaptor molecule 1. Our results suggest the possibility of E144 to serve as a potential anti-neuroinflammatory agent by preventing excess production of pro-inflammatory factors.

Genipin induces mitochondrial dysfunction and apoptosis via downregulation of Stat3/mcl-1 pathway in gastric cancer

BACKGROUND

Genipin is a compound derived from gardenia fruit extract. Although Genipin has anti-tumor effects in various cancers, its effect and mechanism in gastric cancer remain unclear. Here, we investigated the relationship between the anticancer effect of Genipin and signal transducer and activator of transcription (Stat3)/myeloid cell leukemia-1 (Mcl-1) in human gastric cancers.

METHODS

MTT assays were performed to determine the cell viability of gastric cancer and gastric epithelial cell lines (AGS, MKN45, SNU638, MKN74, HFE-145). A TUNEL assay and Western blotting were carried out to investigate apoptosis. Stat3 activity was measured by proteome profiler phospho kinase array, immunofluorescence and immunoblotting. Mitochondria function was monitored with an XF24 analyzer and by flow cytometry, confocal microscopy using fluorescent probes for general mitochondrial membrane potential (MMP).

RESULTS

Genipin induced apoptosis in gastric cancer cells, including AGS and MKN45 cells. Genipin also reduced Mcl-1 mRNA and protein levels. Furthermore, we found that phosphorylation of Stat3 is regulated by Genipin. Additionally, the protein level of phospho Janus kinase 2 (JAK2) was decreased by Genipin treatment, indicating that the Stat3/JAK2/Mcl-1 pathway is suppressed by Genipin treatment in gastric cancer cells. Mcl-1 is closely related to mitochondrial function. These findings suggest that Genipin contributes to the collapse of mitochondrial functions like MMP.

CONCLUSIONS

Genipin induced apoptosis by suppressing the Stat3/Mcl-1 pathway and led to mitochondrial dysfunction. Our results reveal a novel mechanism for the anti-cancer effect of Genipin in gastric cancer.

Thymol polymeric nanoparticle synthesis and its effects on the toxicity of high glucose on OEC cells: involvement of growth factors and integrin-linked kinase

Background

Nowadays, the drug delivery system is important in the treatment of diseases.

Purpose

A polymeric nanoparticle modified by oleic acid (NPMO) as a Thymol (Thy) drug release system was synthesized from Thymbra spicata and its neurotrophic and angiogenic effects on rat’s olfactory ensheathing cells (OECs) in normal (NG) and high glucose (HG) conditions were studied.

Methods

The NPMO was characterized by using different spectroscopy methods, such as infrared, HNMR, CNMR, gel permeation chromatography, dynamic light scattering, and atomic force microscopy. Load and releasing were investigated by HPLC. The toxicity against OECs diet-induced by MTT assay. ROS and generation of nitric oxide (NO) were evaluated using dichloro-dihydro-fluorescein and Griess method, respectively. The expression of protein integrin-linked kinase (ILK), vascular endothelial growth factor (VEGF), brain-derived neurotrophic factor (BDNF), and nerve growth factor (NGF) were evaluated by Western blotting.

Results

ThyNPMO is desirable for transferring drug as a carrier. The amount of Thy and extract (E) loaded on NPMO estimated at 43±2.5% and 41±1.8%, respectively. Then, 65% and 63% of the drug load were released, respectively. Thy, ThyNPMO, E, and ENPMO prevented HG-induced OECs cell death (EC50 33±1.5, 22±0.9, 35±1.8, and 25±1.1 μM, respectively). Incubation with Thy, ThyNPMO, E ,and ENPMO at high concentrations increased cell death with LC50 105±3.5, 82±2.8, 109±4.3, and 86±3.4 μM, respectively in HG states.

Conclusion

OECs were protected by ThyNPMO and ENPMO in protective concentrations by reducing the amount of ROS and NO, maintaining ILK, reducing VEGF, and increasing BDNF and NGF. The mentioned mechanisms were totally reversed at high concentrations.

Self-assembling peptides cross-linked with genipin: resilient hydrogels and self-standing electrospun scaffolds for tissue engineering applications

Self-assembling peptides (SAPs) are synthetic bioinspired biomaterials that can be feasibly multi-functionalized for applications in surgery, drug delivery, optics and tissue engineering (TE). Despite their promising biocompatibility and biomimetic properties, they have never been considered real competitors of polymers and/or cross-linked extracellular matrix (ECM) natural proteins. Indeed, synthetic SAP-made hydrogels usually feature modest mechanical properties, limiting their potential applications, due to the transient non-covalent interactions involved in the self-assembling phenomenon. Cross-linked SAP-hydrogels have been recently introduced to bridge this gap, but several questions remain open. New strategies leading to stiffer gels of SAPs may allow for a full exploitation of the SAP technology in TE and beyond. We have developed and characterized a genipin cross-linking strategy significantly increasing the stiffness and resiliency of FAQ(LDLK)3, a functionalized SAP already used for nervous cell cultures. We characterized different protocols of cross-linking, analyzing their dose and time-dependent efficiency, influencing stiffness, bioabsorption time and molecular arrangements. We choose the best developed protocol to electrospin into nanofibers, for the first time, self-standing, water-stable and flexible fibrous mats and micro-channels entirely made of SAPs. This work may open the door to the development and tailoring of bioprostheses entirely made of SAPs for different TE applications.

Genipin Enhances the Therapeutic Effects of Oxaliplatin by Upregulating BIM in Colorectal Cancer

Despite an increase in the survival rate of patients with cancer owing to the use of current chemotherapeutic agents, adverse effects of cancer therapies remain a concern. Combination therapies have been developed to increase efficacy, reduce adverse effects, and overcome drug resistance. Genipin is a natural product derived from Gardenia jasminoides, which has been associated with anti-inflammatory, anti-angiogenic, and anti-proliferative effects; hypertension; and anti-ischemic brain injuries. However, the enhancement of oxaliplatin sensitivity by genipin remains unexplored. Our study showed that a combination of genipin and oxaliplatin exerts synergistic antitumor effects in vitro and in vivo in colorectal cancer cell lines through the reactive oxygen species (ROS)/endoplasmic reticulum (ER) stress/BIM pathway. Importantly, the combination did not affect normal colon cells. BIM knockdown markedly inhibited apoptosis induced by the combination. In addition, genipin induced ROS by inhibiting superoxide dismutase 3 activity. These findings suggest that genipin may be a novel agent for increasing the sensitivity of oxaliplatin against colorectal cancer. The combination of oxaliplatin and genipin hold significant therapeutic potential with minimal adverse effects.

Crocin, a natural product attenuates lipopolysaccharide-induced anxiety and depressive-like behaviors through suppressing NF-kB and NLRP3 signaling pathway

Depression is one of the foremost psychological illness which is closely leagued with inflammation. Crocin is a natural product that exhibits both anti-inflammatory and anti-oxidant activities. However, little is known about anti-inflammatory mechanisms of crocin on LPS-induced anxiety and depressive-like behaviors. The objective of this study is emphasized on neuroprotective role of crocin against LPS-induced anxiety and depressive-like behaviors in mice. It is observed that crocin inhibited LPS-induced production of NO, TNF-α, IL-1β and ROS in BV-2 microglial cells. Moreover, crocin significantly declined the expression of iNOS, NF-κB p65 and CD16/32 (M1 marker), as well as elevated the expression of CD206 (M2 marker) in BV-2 cell line with decreased LPS-induced anxiety and depressive-like behaviors by improved locomotor activity, reduced sucrose intake, and decreased immobility time in forced swim and tail suspension test in Kunming mice. Expression of NLRP3, ASC and caspase-1 by i.p administration of LPS found to be neutralized with reduction in level of IL-1β, IL-18 and TNF-α in mouse hippocampus. In conclusion, these results suggested that crocin as a potential therapeutic candidate for neuro-inflammation and depressive-like behaviors induced by LPS. The effect was found to be due to inhibition of NLRP3 inflammasome and NF-κB and its promoted M1 to M2 phenotypic conversion of microglia.

Main Human Urinary Metabolites after Genipap (Genipa americana L.) Juice Intake

Genipap (Genipa americana L.) is a native fruit from Amazonia that contains bioactive compounds with a wide range of bioactivities. However, the response to genipap juice ingestion in the human exposome has never been studied. To identify biomarkers of genipap exposure, the untargeted metabolomics approach in human urine was applied. Urine samples from 16 healthy male volunteers, before and after drinking genipap juice, were analyzed by liquid chromatography⁻high-resolution mass spectrometry. XCMS package was used for data processing in the R environment and t-tests were applied on log-transformed and Pareto-scaled data to select the significant metabolites. The principal component analysis (PCA) score plots showed a clear distinction between experimental groups. Thirty-three metabolites were putatively annotated and the most discriminant were mainly related to the metabolic pathways of iridoids and phenolic derivatives. For the first time, the bioavailability of genipap iridoids after human consumption is reported. Dihydroxyhydrocinnamic acid, (1R,6R)-6-hydroxy-2-succinylcyclohexa-2,4-diene-1-carboxylate, hydroxyhydrocinnamic acid, genipic acid, 12-demethylated-8-hydroxygenipinic acid, 3(7)-dehydrogenipinic acid, genipic acid glucuronide, nonate, and 3,4-dihydroxyphenylacetate may be considered biomarkers of genipap consumption. Human exposure to genipap reveals the production of derivative forms of bioactive compounds such as genipic and genipinic acid. These findings suggest that genipap consumption triggers effects on metabolic signatures.

Genome-Wide Expression Profiles Drive Discovery of Novel Compounds that Reduce Binge Drinking in Mice

Transcriptome-based drug discovery has identified new treatments for some complex diseases, but has not been applied to alcohol use disorder (AUD) or other psychiatric diseases, where there is a critical need for improved pharmacotherapies. High Drinking in the Dark (HDID-1) mice are a genetic model of AUD risk that have been selectively bred (from the HS/Npt line) to achieve intoxicating blood alcohol levels (BALs) after binge-like drinking. We compared brain gene expression of HDID-1 and HS/Npt mice, to determine a molecular signature for genetic risk for high intensity, binge-like drinking. Using multiple computational methods, we queried LINCS-L1000 (Library of Integrated Network-Based Cellular Signatures), a database containing gene expression signatures of thousands of compounds, to predict candidate drugs with the greatest potential to decrease alcohol consumption. Our analyses predicted novel compounds for testing, many with anti-inflammatory properties, providing further support for a neuroimmune mechanism of excessive alcohol drinking. We validated the top 2 candidates in vivo as a proof-of-concept. Terreic acid (a Bruton's tyrosine kinase inhibitor) and pergolide (a dopamine and serotonin receptor agonist) robustly reduced alcohol intake and BALs in HDID-1 mice, providing the first evidence for transcriptome-based drug discovery to target an addiction trait. Effective drug treatments for many psychiatric diseases are lacking, and the emerging tools and approaches outlined here offer researchers studying complex diseases renewed opportunities to discover new or repurpose existing compounds and expedite treatment options.

Iridoids and Other Monoterpenes in the Alzheimer's Brain: Recent Development and Future Prospects

Iridoids are a class of monoterpenoid compounds constructed from 10-carbon skeleton of isoprene building units. These compounds in their aglycones and glycosylated forms exist in nature to contribute to mechanisms related to plant defenses and diverse plant-animal interactions. Recent studies have also shown that iridoids and other structurally related monoterpenes display a vast array of pharmacological effects that make them potential modulators of the Alzheimer’s disease (AD). This review critically evaluates the therapeutic potential of these natural products by assessing key in vitro and in vivo data published in the scientific literature. Mechanistic approach of scrutiny addressing their effects in the Alzheimer’s brain including the τ-protein phosphorylation signaling, amyloid beta (Aβ) formation, aggregation, toxicity and clearance along with various effects from antioxidant to antiinflammatory mechanisms are discussed. The drug likeness of these compounds and future prospects to consider in their development as potential leads are addressed.

Geniposide attenuates Aβ25–35-induced neurotoxicity via the TLR4/NF-κB pathway in HT22 cells

Alzheimer's disease (AD), a neurodegenerative disorder, is marked by the accumulation of amyloid-β (Aβ) and neuroinflammation which promote the development of AD. Geniposide, the main ingredient isolated from Chinese herbal medicine Gardenia jasminoides Ellis, has a variety of pharmacological functions such as anti-apoptosis and anti-inflammatory activity. Hence, we estimated the inflammatory cytotoxicity caused by Aβ_25–35 and the neuroprotective effects of geniposide in HT22 cells. In this research, following incubation with Aβ_25–35 (40 μM, 24 h) in HT22 cells, the methylthiazolyl tetrazolium (MTT) and lactate dehydrogenase (LDH) release assays showed that the cell survival rate was significantly decreased. In contrast, the reactive oxygen species (ROS) assay indicated that Aβ_25–35 enhanced ROS accumulation and apoptosis showed in both hoechst 33342 staining and annexin V-FITC/PI double staining. And then, immunofluorescence test revealed that Aβ_25–35 promoted p65 to transfer into the nucleus indicating p65 was activated by Aβ_25–35. Moreover, western blot analysis proved that Aβ_25–35 increased the expression of nitric oxide species (iNOS), tumor necrosis factor-α (TNF-α), cyclooxygenase-2 (COX-2) and interleukin-1β (IL-1β). Simultaneously, Aβ_25–35 also promoted the expression of toll-like receptor 4 (TLR4), p-p65 and p-IκB-α accompanied with the increase in the level of beta-secretase 1 (BACE1) and caspase-3 which further supported Aβ_25–35 induced apoptosis and inflammation. Fortunately, this up-regulation was reversed by geniposide. In conclusion, our data suggest that geniposide can alleviate Aβ_25–35-induced inflammatory response to protect neurons, which is possibly involved with the inhibition of the TLR4/NF-κB pathway in HT22 cells. Geniposide may be the latent treatment for AD induced by neuroinflammation and apoptosis.

Alzheimer's disease (AD), a neurodegenerative disorder, is marked by the accumulation of amyloid-β (Aβ) and neuroinflammation which promote the development of AD.

Genipin inhibits the growth of human bladder cancer cells via inactivation of PI3K/Akt signaling

Genipin, a natural compound derived from the fruit of Gardenia jasminoides, possesses numerous biological properties. The aim of the present study was to investigate the anticancer effects of genipin in human bladder cancer. T24 and 5637 bladder cancer cells were treated with different concentrations of genipin (0-200 µM) and tested for cell viability, colony formation, cell cycle progression and apoptosis. A xenograft model of bladder cancer was established to determine the anticancer effect of genipin in vivo. The involvement of the phosphoinositide-3 kinase (PI3K)/Akt pathway in the action of genipin was examined. Genipin treatment significantly inhibited the viability and clonogenic growth of bladder cancer cells and inhibited the growth of T24 xenograft tumors, compared with vehicle controls (P<0.05). Genipin-treated cells exhibited a cell cycle arrest at the G0/G1-phase, which was accompanied by a deregulation of numerous cell cycle regulators. Genipin-treated cells demonstrated a significant increase in the percentage of apoptotic cells, loss of mitochondrial membrane potential, Bax translocation to the mitochondria and the release of cytochrome c to the cytosol. Additionally, genipin treatment significantly (P<0.05) reduced the phosphorylation levels of PI3K and Akt in bladder cancer cells. Importantly, genipin-mediated anticancer effects were reversed by the overexpression of constitutively active Akt. In conclusion, to the best of our knowledge, the present study demonstrates for the first time the growth inhibitory effects of genipin in bladder cancer cells, and indicates its potential as a natural anticancer agent for bladder cancer.

Uncoupling Protein 2 Inhibition Exacerbates Glucose Fluctuation-Mediated Neuronal Effects

Though glucose fluctuations have been considered as an adverse factor for the development of several diabetes-related complications, their impact in the central nervous system is still not fully elucidated. This study was conducted to evaluate the responses of neuronal cells to different glycemic exposures alongside to elucidate the role of uncoupling protein 2 (UCP2) in regulating such responses. To achieve our goals, primary cortical neurons were submitted to constant high (HG)/low (LG) or glucose level variations (GVs), and the pharmacological inhibition of UCP2 activity was performed using genipin. Results obtained show that GV decreased neuronal cells' viability, mitochondrial membrane potential, and manganese superoxide dismutase activity and increased reactive oxygen species (ROS) production. GV also caused an increase in the glutathione/glutathione disulfide ratio and in the protein expression levels of nuclear factor E2-related factor 2 (NRF2), UCP2, NADH-ubiquinone oxidoreductase chain 1 (ND1), and mitochondrially encoded cytochrome c oxidase I (MTCO1), both mitochondrial DNA encoded subunits of the electron transport chain. Contrariwise, genipin abrogated all those compensations and increased the levels of caspase 3-like activity, potentiated mitochondrial ROS levels, and the loss of neuronal synaptic integrity, decreased the protein expression levels of NRF1, and increased the protein expression levels of UCP5. Further, in the control and LG conditions, genipin increased mitochondrial ROS and the protein expression levels of UCP4, postsynaptic density protein 95 (PSD95), ND1, and MTCO1. Overall, these observations suggest that UCP2 is in the core of neuronal cell protection and/or adaptation against GV-mediated effects and that other isoforms of neuronal UCPs can be upregulated to compensate the inhibition of UCP2 activity.

Treatment Effects of Ischemic Stroke by Berberine, Baicalin, and Jasminoidin from Huang-Lian-Jie-Du-Decoction (HLJDD) Explored by an Integrated Metabolomics Approach

Berberine, baicalin, and jasminoidin were major active ingredients of Huang-Lian-Jie-Du-Decoction (HLJDD), a famous prescription of traditional Chinese medicine (TCM), which has been used for the treatment of ischemic stroke. The aim of the present study was to classify their roles in the treatment effects of ischemic stroke. A rat model of middle cerebral artery occlusion (MCAO) was constructed to mimic ischemic stroke and treatment effects of berberine, baicalin, and jasminoidin, and HLJDD was assessed by neurologic deficit scoring, infarct volume, histopathology, immunohistochemistry, biochemistry, quantitative real-time polymerase chain reaction (qRT-PCR), and Western blotting. In addition, the ¹H NMR metabolomics approach was used to assess the metabolic profiles, which combined with correlation network analysis successfully revealed metabolic disorders in ischemic stroke concerning the treatment of the three principal compounds from HLJDD for the first time. The combined results suggested that berberine, baicalin, and jasminoidin are responsible for the effectiveness of HLJDD on the treatment of ischemic stroke by amelioration of abnormal metabolism and regulation of oxidative stress, neuron autophagy, and inflammatory response. This integrated metabolomics approach showed its potential in understanding the function of complex formulae and clarifying the role of its components in the overall treatment effects.

Allergic contact dermatitis caused by a new temporary blue-black tattoo dye - sensitization to genipin from jagua (Genipa americana L.) fruit extract

BACKGROUND

Temporary tattoos made with an extract of the jagua fruit (Genipa americana L.) are becoming increasingly popular. It is claimed that it is 'dermatologically tested' and does not contain p-phenylenediamine. Extracts of jagua and gardenia fruits have been used by indigenous people in South America, as well as in traditional Chinese medicine, for centuries. Genipin is currently used for its cross-linking effect in the manufacture of polysaccharides, and is being investigated for its anti-inflammatory and other properties.

OBJECTIVES

To report the presence of the allergenic substance genipin in a self-administered temporary tattoo dye made from the fruit juice of jagua (Genipa americana L.).

PATIENTS AND METHODS

A 39-year-old female who repeatedly applied 'completely natural and 100% safe' Earth Jagua® tattoo, obtained via the internet, to her left hand developed allergic contact dermatitis within 6 weeks. Analysis of the dye showed the presence of geniposide and genipin.

RESULTS

Patch tests with the dye and with its main components, including genipin, gave strong positive reactions to the latter. There was no sensitization to other ingredients or p-amino compounds.

CONCLUSIONS

We report an extensively evaluated case of allergic contact dermatitis caused by a temporary Earth Jagua® tattoo. The allergen identified is genipin, a substance that is increasingly used for tattoos and as a therapeutic agent in medicine. This could result in an increase in the number of allergic reactions in the future.

Protective Effects of Genipin on Gastrointestinal Disorders

Genipin, an aglycone of geniposide, is a major component of gardeniae fructus, and has been used to treat jaundice, various inflammatory disorders, and liver disease, and has also been used as a natural cross-linking agent. The authors conducted several experiments to evaluate the protective effects of genipin on gastrointestinal disorders, such as, gastritis and gastric ulcers. Genipin showed inhibitory effects against HCl·ethanol-induced acute gastritis and indomethacin-induced gastric ulcers in rats and increased prostaglandin E₂ (PGE₂) in AGS gastric cancer cell. Genipin had significant effects on aggressive factors, acid-neutralization, and gastric secretion, and inhibited H⁺/K⁺-ATPase (a proton pump), which secretes gastric acid. The results obtained indicate that genipin has significant gastroprotective effects and might be useful for treating and preventing gastric lesions.

Biologically active and biomimetic dual gelatin scaffolds for tissue engineering

We have designed, developed and optimized Genipin cross-linked 3D gelatin scaffolds that were biologically active and biomimetic, show a dual activity both for growth factor and cell delivery. Type B gelatin powder was dissolved in DI water. 100mg of genipin was dissolved in 10ml of DI water. Three genipin concentrations were prepared: 0.1%, 0.2% and 0.3% (w/v). Solutions were mixed at 40°C and under stirring and then left crosslinking for 72h. Scaffolds were obtained by punching 8 mm-cylinders into ethanol 70% solution for 10min and then freeze-drying. Scaffolds were biologically, biomechanically and morphologically evaluated. Cell adhesion and morphology of D1-Mesenchymal stem cells (MSCs) and L-929 fibroblast was studied. Vascular endothelial grwoth factor (VEGF) and Sonic hedgehog (SHH) were used as model proteins. Swelling ratio increased and younǵs module decreased along with the concentration of genipin. All scaffolds were biocompatible according to the toxicity test. MSC and L-929 cell adhesion improved in 0.2% of genipin, obtaining better results with MSCs. VEGF and SHH were released from the gels. This preliminary study suggest that the biologically active and dual gelatin scaffolds may be used for tissue engineering approaches like bone regeneration.