Toxicology study of vanillin on rats via oral and intra-peritoneal administration

In vitro cytotoxicity and genotoxicity assessment of methanolic extracts of vanillas from Brazilian biodiversity with commercial potential

The Vanilla genus is crucial for global production in food, perfume, and pharmaceutical industries. However, exploitation threatens some species, leading to extinction. Traditional communities use vanilla for medicinal purposes, and there are species like Vanilla chamissonis Klotzsch and Vanilla bahiana Hoehne with potential to occupy the market. For this, methanolic extraction of these two mentioned species was conducted alongside Vanilla planifolia. Analyzes of the cell viability, mutagenic and genotoxic potential were performed. In the Ames test, the assays were performed with concentrations from 0.5 and 5000 μg/ml and on five strains. Only Vanilla planifolia exhibited mutagenicity at the highest concentration in the TA98 strain. Viability tests were performed within a dose range of 0.05-5000 µg/ml and 24, 48, and 72-hour exposures. It was possible to observe a reduction in cell viability observed only at the highest concentration, for all three species and both cell types tested. Genotoxicity induction by the extracts was assessed at concentrations from 0.5 to 500 µg/ml through the cytokinesis-block micronucleus assay. No genotoxic damage or reduction in the Nucleus Division Index (NDI). The study found no mutagenicity, cytotoxicity, or genotoxicity in the species tested, indicating potential human use for food or pharmaceutical purposes.

Development of dietary small molecules as multi-targeting treatment strategies for Alzheimer's disease

Cognitive dysfunction can occur both in normal aging and age-related neurological disorders, such as mild cognitive impairment and Alzheimer's disease (AD). These disorders have few treatment options due to side effects and limited efficacy. New approaches to slow cognitive decline are urgently needed. Dietary interventions (nutraceuticals) have received considerable attention because they exhibit strong neuroprotective properties and may help prevent or minimize AD symptoms. Biological aging is driven by a series of interrelated mechanisms, including oxidative stress, neuroinflammation, neuronal apoptosis, and autophagy, which function through various signaling pathways. Recent clinical and preclinical studies have shown that dietary small molecules derived from natural sources, including flavonoids, carotenoids, and polyphenolic acids, can modulate oxidative damage, cognitive impairments, mitochondrial dysfunction, neuroinflammation, neuronal apoptosis, autophagy dysregulation, and gut microbiota dysbiosis. This paper reviews research on different dietary small molecules and their bioactive constituents in the treatment of AD. Additionally, the chemical structure, effective dose, and specific molecular mechanisms of action are comprehensively explored. This paper also discusses the advantages of using nanotechnology-based drug delivery, which significantly enhances oral bioavailability, safety, and therapeutic effect, and lowers the risk of adverse effects. These agents have considerable potential as novel and safe therapeutic agents that can prevent and combat age-related AD.

Ameliorative effects of vanillin against pentylenetetrazole-induced epilepsy and associated memory loss in mice: The role of Nrf2/HO-1/NQO1 and HMGB1/RAGE/TLR4/NFκB pathways

BACKGROUND

Epilepsy is a severe neurological disorder associated with substantial morbidity and mortality. Vanillin (Van) is a natural phenolic aldehyde with beneficial pharmacological properties. This study investigated the neuroprotective effects of Van in epilepsy and elucidated its mechanism of action.

METHODS

Swiss albino mice were divided into the following five groups: "normal group", 0.9 % saline; "pentylenetetrazole (PTZ) group", intraperitoneal administration of 35 mg/kg PTZ on alternate days up to 42 days; and "PTZ + Van 20", "PTZ + Van 40", and "PTZ + sodium valproate (Val)" groups received PTZ injections in conjunction withVan 20 mg, Van 40 mg/kg, and Val 300 mg/kg, respectively. Behavioural tests and hippocampal histopathological analysis were performed in all groups. The Nrf2/HO-1/NQO1 and HMGB1/RAGE/TLR4/NFκB pathways, oxidative stress, neuro-inflammation, and apoptotic markers were analysed. Furthermore, brain acetylcholinesterase (AChE) activity and levels of dopamine (DA), gamma-aminobutyric acid GABA, and serotonin 5-HT were assessed.

RESULTS

Van prolonged seizure manifestations and improved electroencephalogram (EEG)criteriain conjunction with 100 mg/kg PTZ once daily. Van administration increased Nrf2/HO-1/NQO1 levels, with subsequent attenuation of malondialdehyde (MDA) and nitric oxide (NO) levels with elevated glutathione (GSH) levels and intensified superoxide dismutase (SOD) and catalase activities. Van reduced the gene and protein expression of HMGB1/RAGE/TLR4/NFκB and decreased the levels of inflammatory and apoptotic markers. In addition, Van reduced AChE activity, and elevated glial fibrillary acidic proteins (GFAP) increased neurotransmitter and brain-derived neurotrophic factors (BDNF).

CONCLUSION

By increasing Nrf2/HO-1/NQO1 levels and downregulating the HMGB1/RAGE/TLR4/ NFκB pathway, Van offered protection in PTZ-kindled mice with subsequent attenuation in lipid peroxidation, upregulation in antioxidant enzyme activities, and reduction in inflammation and apoptosis.

Vanillin attenuates CdCl2-induced cytotoxicity in isolated human erythrocytes

Cadmium is a toxic heavy metal with no physiological role in the human body. Cadmium has high mobility due to its widespread industrial use, with no safe and effective therapeutic management. Cadmium toxicity manifests by increasing oxidative stress in target cells. We have explored the potential role of vanillin, a plant phenolic aldehyde and antioxidant, in mitigating cadmium chloride (CdCl2) induced hemotoxicity using isolated human erythrocytes. CdCl2 was added to erythrocytes, in the absence and presence of vanillin. Incubation of erythrocytes with CdCl2 alone inhibited methemoglobin reductase and enhanced methemoglobin level. Heme degradation and release of free iron (Fe2+), along with protein and membrane lipid oxidation, were also increased. A CdCl2-induced enhancement in reactive oxygen and nitrogen species was also seen, lowering the overall antioxidant power of cells. However, pre-incubation of erythrocytes with vanillin resulted in significant decreased generation of reactive species and prevented heme degradation and heme oxidation. Vanillin augmented the erythrocyte antioxidant capacity and reinstated the activities of major antioxidant, plasma membrane-bound and glucose metabolism enzymes. Scanning electron microscopy showed that CdCl2 treatment led to the formation of echinocytes which was prevented by vanillin. In all cases, no harmful effects of vanillin alone were seen. Thus, vanillin alleviates the toxicity of cadmium and can be potentially employed as a chemoprotectant against the damaging effects of this heavy metal.

Overview of the Role of Vanillin in Neurodegenerative Diseases and Neuropathophysiological Conditions

Nowadays, bioactive natural products play key roles in drug development due to their safety profile and strong antioxidant power. Vanillin is a natural phenolic compound found in several vanilla beans and widely used for food, cosmetic, and pharmaceutical products. Besides its industrial applications, vanillin possesses several beneficial effects for human health, such as antioxidant activity in addition to anti-inflammatory, anti-mutagenic, anti-metastatic, and anti-depressant properties. Moreover, vanillin exhibits neuroprotective effects on multiple neurological disorders and neuropathophysiological conditions. This study reviews the mechanisms of action by which vanillin prevents neuroinflammation and neurodegeneration in vitro and in vivo systems, in order to provide the latest views on the beneficial properties of this molecule in chronic neurodegenerative diseases and neuropathophysiological conditions.

Molecular dynamics simulation, synthesis and topoisomerase inhibitory actions of vanillin derivatives: a systematic computational structural integument

A series of 4-hydroxy-3-methoxy benzaldehyde (vanillin) derivatives (3a-3r) was designed for the principle of Schiff base condensation with several individual sulfanilamide analogues. The inhibitory potencies of the designed compounds were evaluated through molecular docking simulation studies against the targets, breast cancer-topo isomerase-IIα and estrogen receptor-α; and the top scoring poses with higher binding energy were selected to assess the mode of binding and stability of each complex through molecular dynamics simulations. Compounds that remained stable in the active sites of the both target receptors through a number of strong H-bonds and hydrophobic contacts were selected. Based on the computational results, these selected compounds, 3b, 3e and 3f were synthesized and were followed up for structural elucidation attempts, by FT/ATR, ¹H NMR and ¹³C NMR. From the experimental in vitro studies on 3b, 3e and 3f, the following remarkable activities against breast cancer cell line were done; IC₅₀ values of 3b, 3e and 3f were noted, 6.7, 4.3 and 11 ng/mL, respectively. These newly synthesized compounds may be used as novel inhibitors of nuclear receptors with potential therapeutic applications in control of cancer.Communicated by Ramaswamy H. Sarma.

Mechanistic insights into the inhibitory activities of chemical constituents from the fruits of Terminalia boivinii on α-glucosidase

Regulation of key digestive enzymes is currently considered an effective remedy for diabetes mellitus. In this study, bioactive constituents were purified from Terminalia boivinii fruits and identified by 1 H NMR, 13 C NMR and EI-MS. In vitro and in silico methods were used to evaluate α-glucosidase, α-amylase, and lipase inhibition activities. Compounds 1 , 2 , and 4-7 with IC50 values between 89 and 445 µM showed stronger α-glucosidase inhibitory activities than the antihyperglycemic drug acarbose (IC 50 =1463.0 ± 29.5 µM). However, the compounds showed lower inhibitory effects against α-amylase and lipase with IC 50 values above 500 µM than acarbose (IC 50 = 16.7 ± 3.5 µM) and ursolic acid (IC 50 = 89.5 ± 5.6 µM), respectively. Lineweaver-Burk plots showed that compounds 1 , 2 , and 7 were non-competitive inhibitors, compounds 4 and 5 were competitive inhibitors and compound 6 was a mixed-type inhibitor. Fluorescence spectroscopic data showed that the compounds altered the microenvironment and conformation of α-glucosidase. Computer simulations indicated that the compounds and enzyme interacted primarily through hydrogen bonding. The findings indicated that the compounds were inhibitors of α-glucosidase and provided significant structural basis for understanding the binding activity of the compounds with α-glucosidase.

Vanillin augments liver regeneration effectively in Thioacetamide induced liver fibrosis rat model

AIMS

This study has been designed to investigate the role of vanillin either as prophylaxis or treatment in liver regeneration augmentation and liver fibrosis regression in thioacetamide (TAA) induced liver damage.

MATERIALS AND METHODS

Animals were injected with TAA to induce liver injury (200mg/kg twice weekly) for 8 weeks. In vanillin prophylaxis group; rats were administered vanillin (100 mg/Kg; IP, daily) from day 1 of TAA injection for 8 weeks. In vanillin treatment group; rats were confronted with the same dose of TAA injection for 8 weeks then treated with vanillin (100 mg/Kg, IP, daily) for 4 weeks. ALT, AST activities, serum albumin, hepatic GSH, MDA, HGF, VEGF, IL-6 and TNF-α levels were measured and also, MMP-2, TIMP-1 and cyclin D gene expression were determined. Liver sections were stained with H&E and Sirius red and immunostained for Ki-67 and α-SMA for histological and immunohistological changes analysis.

KEY FINDINGS

Vanillin improved liver function and histology. Also, showed a remarkable increase in hepatic HGF and VEGF level, and up-regulation of cyclin D1 expression accompanied by a significant up-regulation of MMP-2 and down- regulation of TIMP-1. All these effects were accompanied by TNF-α, IL-6 and oxidative stress significant attenuation.

SIGNIFICANCE

In conclusion, vanillin enhanced liver regeneration in TAA induced liver damage model; targeting growth factors (HGF, VEGF) and cellular proliferation marker cyclin D1. As well as stimulating fibrosis regression by inhibition of ECM accumulation and enhancing its degradation.

Vanillin modulates activities linked to dysmetabolism in psoas muscle of diabetic rats

Skeletal muscles are important in glucose metabolism and are affected in type 2 diabetes (T2D) and its complications. This study investigated the effect of vanillin on redox imbalance, cholinergic and purinergic dysfunction, and glucose-lipid dysmetabolism in muscles of rats with T2D. Male albino rats (Sprague-Dawley strain) were fed 10% fructose ad libitum for 2 weeks before intraperitoneally injecting them with 40 mg/kg streptozotocin to induce T2D. Low (150 mg/kg bodyweight (BW)) and high (300 mg/kg BW) doses of vanillin were orally administered to diabetic rats. Untreated diabetic rats and normal rats made up the diabetic control (DC) and normal control (NC) groups, respectively. The standard antidiabetic drug was metformin. The rats were humanely put to sleep after 5 weeks of treatment and their psoas muscles were harvested. There was suppression in the levels of glutathione, activities of SOD, catalase, ENTPDase, 5'Nucleotidase and glycogen levels on T2D induction. This was accompanied by concomitantly elevated levels of malondialdehyde, serum creatine kinase-MB, nitric oxide, acetylcholinesterase, ATPase, amylase, lipase, glucose-6-phosphatase (G6Pase), fructose-1,6-biphophastase (FBPase) and glycogen phosphorylase activities. T2D induction further resulted in the inactivation of fatty acid biosynthesis, glycerolipid metabolism, fatty acid elongation in mitochondria and fatty acid metabolism pathways. There were close to normal and significant reversals in these activities and levels, with concomitant reactivation of the deactivated pathways following treatment with vanillin, which compared favorably with the standard drug (metformin). Vanillin also significantly increased muscle glucose uptake ex vivo. The results suggest the therapeutic effect of vanillin against muscle dysmetabolism in T2D as portrayed by its ability to mitigate redox imbalance, inflammation, cholinergic and purinergic dysfunctions, while modulating glucose-lipid metabolic switch and maintaining muscle histology.

Potential Effects of Phenolic Compounds That Can Be Found in Olive Oil on Wound Healing

The treatment of tissue damage produced by physical, chemical, or mechanical agents involves considerable direct and indirect costs to health care systems. Wound healing involves a series of molecular and cellular events aimed at repairing the defect in tissue integrity. These events can be favored by various natural agents, including the polyphenols in extra virgin olive oil (EVOO). The objective of this study was to review data on the potential effects of different phenolic compounds that can also be found in EVOO on wound healing and closure. Results of in vitro and animal studies demonstrate that polyphenols from different plant species, also present in EVOO, participate in different aspects of wound healing, accelerating this process through their anti-inflammatory, antioxidant, and antimicrobial properties and their stimulation of angiogenic activities required for granulation tissue formation and wound re-epithelialization. These results indicate the potential usefulness of EVOO phenolic compounds for wound treatment, either alone or in combination with other therapies. Human studies are warranted to verify this proposition.

Vanillin exerts therapeutic effects against hyperglycemia-altered glucose metabolism and purinergic activities in testicular tissues of diabetic rats

Testicular dysfunctions leading to male infertility has been reported in type 2 diabetes (T2D), with glucose dysmetabolism, cholinergic and purinergic dysfunction being major contributors. In the present study, the effect of vanillin on glucose metabolism, purinergic and cholinergic dysfunctions were investigated in testicular tissues of T2D rats. Male Sprague-Dawley rats were divided into 6 groups containing 5 rats each. T2D was induced in rats by administering 10 % fructose ad libitum for 14 days followed by a single intraperitoneal injection (40 mg/kg body weight) of streptozotocin. T2D rats were orally administered with vanillin at 150 and 300 mg/kg body weight (bw). Diabetic control (DC) consisted of untreated diabetic rats, while normal control (NC) consisted of normal rats and they were administered with distilled water only. Metformin was used as the standard antidiabetic drug. After 5 weeks treatment, the rats were sacrificed, and the testes were harvested. Induction of T2D led to significantly depleted testicular levels of glutathione, glycogen content, superoxide dismutase and catalase enzyme activities, with concomitantly elevated levels of nitric oxide, malondialdehyde, acetylcholinesterase, glucose-6-phosphatase, fructose-1,6-biphophastase, glycogen phosphorylase, amylase and lipase activities. These activities and levels were significantly reversed to near normal in rats treated with both doses of vanillin as compared with metformin. These results, when taken together, suggest the therapeutic effect of vanillin against hyperglycemia-mediated metabolic dysfunctions in testes of T2D rats. This is depicted by the ability of the phenolic to attenuate oxidative imbalance, purinergic and cholinergic dysfunctions, while suppressing glucose dysmetabolism.

Vanillin: a review on the therapeutic prospects of a popular flavouring molecule

Abstract

Graphic abstract

Synergistic antioxidant capacities of vanillin and chitosan nanoparticles against reactive oxygen species, hepatotoxicity, and genotoxicity induced by aging in male Wistar rats

This study aimed to evaluate the synergistic effects of both vanillin (V) and chitosan nanoparticles (CNPs) in alleviating hepatotoxicity, oxidative injury, and genotoxicity induced by d-galactose (DG) and resulted from aging in male albino rats. Male Wistar rats were divided into seven groups (10 rats/group) as follows: control group, (DG) group (100 mg/kg), (V) group (100 mg/kg), CNPs either (low dose (LD) or CNPs (high dose (HD) (140 mg/kg) and (280 mg/kg), and CNPs (LD and HD) dose with V- and DG plus V-treated groups. The CNPs were characterized by transmission electron microscopy (TEM), zeta potential, and size distribution of nanoparticles. After 60 consecutive days of exposure, some biochemical parameters were measured as hepatic aminotransferases enzymes, lipid profile, tumor necrosis factor alpha, interleukin-6 (IL-6), markers of inflammation, tissue damage lactate dehydrogenase, C-reactive protein (CRP), mitochondrial potential activities, myeloperoxidase, xanthine oxidase, CRP, succinate dehydrogenase, mitochondria membrane potential, malondialdehyde levels and antioxidant enzymes (superoxide dismutase, catalase, glutathione reductase, and glutathione S-transferase), and adenosine triphosphate content with histological, alkaline comet assay, and TEM examination of the hepatic tissues. CNPs showed that size distribution (polydispersity index) 0.350 nm and the zeta potential measurement of CNPs were found to be -14.9 mV which revealed the high stability of CNPs. DG induced biochemical and cellular alterations in the hepatic tissues. CNPs and V synergistically afforded protection against hepatic injury and oxidative stress resulting from aging that was induced by DG. Consequently, CNPs were an effective agent in the drug delivery in the hepatic diseases medications and act as a carrier for V and thus make synergistic effect between CNPs and V that achieved the high antioxidant capacities. CNPs and V improved the hepatic enzymes, which act as anti-inflammatory and antigenotoxicity, and improved the antioxidant capacities in the hepatic tissues.

Vanillin Prevents Doxorubicin-Induced Apoptosis and Oxidative Stress in Rat H9c2 Cardiomyocytes

Doxorubicin (doxo) is an effective anticancer compound in several tumor types. However, as a consequence of oxidative stress induction and ROS overproduction, its high cardiotoxicity demands urgent attention. Vanillin possesses antioxidant, antiproliferative, antidepressant and anti-glycating properties. Therefore, we investigated the potential vanillin protective effects against doxo-induced cardiotoxicity in H9c2 cells. Using multiparametric approach, we demonstrated that vanillin restored both cell viability and damage in response to doxo exposure. Contextually, vanillin decreased sub-G1 appearance and caspase-3 and PARP1 activation, reducing the doxo-related apoptosis induction. From a mechanistic point of view, vanillin hindered doxo-induced ROS accumulation and impaired the ERK phosphorylation. Notably, besides the cardioprotective effects, vanillin did not counteract the doxo effectiveness in osteosarcoma cells. Taken together, our results suggest that vanillin ameliorates doxo-induced toxicity in H9c2 cells, opening new avenues for developing alternative therapeutic approaches to prevent the anthracycline-related cardiotoxicity and to improve the long-term outcome of antineoplastic treatment.

Neurotoxicity of e-cigarettes

It appears that electronic cigarettes (EC) are a less harmful alternative to conventional cigarette (CC) smoking, as they generate substantially lower levels of harmful carcinogens and other toxic compounds. Thus, switching from CC to EC may be beneficial for smokers. However, recent accounts of EC- or vaping-associated lung injury (EVALI) has raised concerns regarding their adverse health effects. Additionally, the increasing popularity of EC among vulnerable populations, such as adolescents and pregnant women, calls for further EC safety evaluation. In this state-of-the-art review, we provide an update on recent findings regarding the neurological effects induced by EC exposure. Moreover, we discuss possible neurotoxic effects of nicotine and numerous other chemicals which are inherent both to e-liquids and EC aerosols. We conclude that in recognizing pertinent issues associated with EC usage, both government and scientific researchers must address this public health issue with utmost urgency.

Neuroprotective effect of Vanillin on hypoxic-ischemic brain damage in neonatal rats

Neonatal hypoxic-ischemic brain damage (HIBD) is a leading cause of death and perpetual neurological dysfunction in neonates. Vanillin (Van), a natural phenolic compound with neuroprotective properties, exerts neuroprotection on a gerbil model of global ischemia by inhibiting oxidative damage. This study aimed to explore the potential neuroprotective roles of Van in neonatal rats suffering from hypoxic-ischemic (HI). An HI model of 7-day-old SD rats was induced by left carotid artery ligation followed by exposure to 8% oxygen (balanced with nitrogen) for 2.5 h at 37 °C. At 48 h after intraperitoneal injection with Van (20, 40, and 80 mg/kg) or saline, neurobehavioral function, cerebral infract volume, brain water content, and histomorphological changes were performed to evaluate brain injury. Transmission electron microscopy and immunoglobulin G (IgG) staining were conducted to evaluate the integrity of the blood-brain barrier (BBB). The levels of oxidative stress and tight junction proteins, as well as the activities of matrix metalloproteinases (MMPs), were also determined in the ipsilateral hemisphere. Results showed that Van post-treatment significantly ameliorated early neurobehavioral deficits, decreased infarct volume and brain edema, as well as attenuated histopathologic injury and IgG extravasation. Furthermore, Van markedly increased the activities of endogenous antioxidant enzymes and decreased malondialdehyde content. Meanwhile, the activation of MMP-2 and MMP-9 induced by HI was partially blocked by Van. Finally, Van obviously increased the expression of ZO-1, Occludin, and Claudin-5 compared with the HI group. Collectively, Van can provide neuroprotective effects against neonatal HIBD possibly by attenuating oxidative damage and preserving BBB integrity.

Comprehensive behavioral study of the effects of vanillin inhalation in mice

Vanillin is widely used in food and cosmetics, among other substances, for its sweet smell. However, the neuropsychological effects of vanillin inhalation have not been elucidated. In this study, we investigated the effect of vanillin inhalation on mouse behavior. First, we investigated whether the aroma of vanillin was attractive or repulsive for mice. Thereafter, the mice inhaled vanillin for 20 min before each test in a series of behavioral tests (elevated plus maze, open field, Y-maze, tail suspension, cotton bud biting, and Porsolt forced swim tests). In these tests, the mice showed a neutral response to vanillin. Mice that inhaled vanillin had a suppressed pain response in the hot plate test. In addition, the grip strength of the forelimbs of mice that inhaled vanillin was decreased. No significant differences were found between the mice inhaling vanillin and control mice in the open field, Y-maze, tail suspension, forced swimming, and aggression tests. These results show that vanillin inhalation has anti-nociceptive effects, similar to other routes of administration. The results also show that vanillin inhalation does not cause significant behavioral effects.

Hepatotoxicity and nephrotoxicity in rats induced by carbon tetrachloride and the protective effects of Teucrium polium and vitamin C

This work investigated the protective effects of Teucrium polium (T. polium) and vitamin C (Vit C) against carbon tetrachloride (CCl₄) induced hepatotoxicity and nephrotoxicity in rats. T. polium reduced the Fer reduced antioxidant power (FRAP) (IC₅₀ = 0.89 mg/ml) and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) (IC₅₀ = 0.049 µg/ml) than Vit C, FRAP (IC₅₀ = 0.71 mg/ml) and DPPH (IC₅₀ = 0.029 µg/ml). Male albino Wistar rats were divided into six groups: Group I was used as controls, Group II received CCl₄ in olive oil (0.5 ml/kg) by gavage, Group III received CCl₄ in olive oil (0.5 ml/kg) by gavage after 3 d of receiving T. polium (5 g/l), orally, Group IV received T. polium (5 g/l) alone, by gavage, for 7 d, Group V received CCl₄ in olive oil (0.5 ml/kg) by gavage after 3 d of receiving Vit C (250 mg/kg) by gavage and Group VI received Vit C (250 mg/kg) alone by gavage. CCl₄ showed an increase of serum hepatic and renal markers aspartate aminotransferase (AST), alanine aminotransferase (ALT), urea, and creatinine. Moreover, we noted an increase of lipid peroxidations and a decrease in antioxidants enzymes: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) of CCl₄ rats compared to controls. The pretreatment with (200 mg/kg) of T. polium and with Vit C (250 mg/kg) by gavage, for 7 d, displayed their ability to protect against oxidative damage and biochemical changes induced by CCl₄. Our results were in accordance with histopathological observations.

Vanillin-Ameliorated Development of Azoxymethane/Dextran Sodium Sulfate-Induced Murine Colorectal Cancer: The Involvement of Proteasome/Nuclear Factor-κB/Mitogen-Activated Protein Kinase Pathways

Vanillin is a natural dietary flavoring widely used in the food industry. Colorectal cancer (CRC) is one of the common malignancies in the world. Chronic intestinal inflammation is a risk factor for the development of CRC. We have previously found that vanillin improves and prevents colitis in mice. Here we evaluated the inhibitory activities of vanillin on a mouse model of colitis-induced CRC. Mice were challenged intraperitoneally with azoxymethane (AOM) and orally with dextran sodium sulfate (DSS). Various dosages of vanillin were orally administered for 13 consecutive weeks. Vanillin alleviated the development of tumors in AOM/DSS-induced mice. The total number of tumors in 100 mg/kg vanillin group was significantly reduced by 57.14 ± 7.67%, compared with sham group. Gene expression analysis showed that vanillin downregulated the expression levels of proteasome genes in colon tissues. Moreover, vanillin at 10 mM significantly suppressed proteasome activities in HCT-116 cells by 41.27 ± 0.41%. Furthermore, vanillin diminished the phosphorylation of mitogen-activated protein kinases (MAPKs) and reduced the number of p65-positive cells, proliferating cells, and granulocytes in colon tissues with statistical significance. In conclusion, our data suggested that vanillin was a bioactive compound that ameliorated the development of AOM/DSS-induced colon cancer in mice. Moreover, the amelioration of vanillin might be associated with the downregulation of proteasome, nuclear factor-κB, and MAPK pathways.

Oral Administration of Vanillin Improves Imiquimod-Induced Psoriatic Skin Inflammation in Mice

Vanillin is one of the most widely used flavoring products worldwide. Psoriasis is a chronic inflammatory skin disorder. The interleukin-23 (IL-23)/interleukin-17 (IL-17) axis plays a critical role in psoriasis. Here, we analyzed the effect of vanillin on imiquimod (IMQ)-induced psoriatic skin inflammation in mice. Mice were treated topically with IMQ on the back skin and orally with various amounts of vanillin for 7 consecutive days. Vanillin significantly improved IMQ-induced histopathological changes of skin in a dose-dependent manner. The thickness and number of cell layers of epidermis were reduced by 29 ± 14.4 and 27.8 ± 11%, respectively, in mice given 100 mg/kg of vanillin. A microarray showed that a total of 9042 IMQ-upregulated genes were downregulated by vanillin, and the biological pathways involved in the immune system and metabolism were significantly altered by vanillin. The upregulated expressions of IL-23, IL-17A, and IL-17F genes were suppressed by vanillin, with fold changes of -3.07 ± 0.08, -2.06 ± 0.21, and -1.62 ± 0.21, respectively. Moreover, vanillin significantly decreased both the amounts of IL-17A and IL-23 and the infiltration of immune cells in the skin tissues of IMQ-treated mice. In conclusion, our findings suggested that vanillin was an effective bioactive compound against psoriatic skin inflammation. Moreover, the downregulation of IL-23 and IL-17 expression suggested that vanillin was a novel regulator of the IL-23/IL-17 axis.

Vanillin abrogates ethanol induced gastric injury in rats via modulation of gastric secretion, oxidative stress and inflammation

Vanillin is commonly used as an additive in food, medicine and cosmetics, but its effect has not yet been studied in gastric injury. Therefore the effect of vanillin was studied in experimental gastric ulcer. Gastric secretion and acidity were studied in pylorus ligated rats. Ulcer index, levels of gastric mucus, malondialdehyde (MDA), myeloperoxidase activity (MPO), expression of nuclear factor kappa B (NF-κB) p65, and histopathological changes were determined in ethanol induced gastric ulcer. Pre treatment with vanillin significantly reduced gastric secretion (P < 0.001) and acidity (P < 0.0001) and gastric ulcer index scores (P < 0.001). and augmented the gastric mucosal defense. Vanillin significantly restored the depleted gastric wall mucus levels (P < 0.0001) induced by ethanol and also significantly attenuated ethanol induced inflammation and oxidative stress by the suppression of gastric MPO activity (P < 0.001), reducing the expression of NF-κB p65 and the increased MDA levels (P < 0.001). Vanillin was also effective in alleviating the damage to the histological architecture and the activation of mast cells induced by ethanol.

Together the results of this study highlight the gastroprotective activity of vanillin in gastric ulcers of rats through multiple actions that include inhibition of gastric secretion and acidity, reduction of inflammation and oxidative stress, suppression of expression of NF-κB, and restoration of the histological architecture.

Fabrication of chitosan microspheres using vanillin/TPP dual crosslinkers for protein antigens encapsulation

Microspheres were prepared from water soluble chitosan using dual vanillin/TPP crosslinkers. Placebo (C1), Bovine serum albumin (BSA) (C2), monovalent tetanus toxoid (TT) (C3) and divalent tetanus (TT) and diphtheria toxoids (DT) (C4) encapsulated microspheres were studied in terms of size (1-4 μm), encapsulation efficiency (75-80%), swelling and mucoadhesion (56-68%). FT-IR, TGA, XRD and SEM characterization of microspheres suggested specific interaction, more thermal stability, amorphous nature and rough surfaces of encapsulated microspheres. EDS confirmed the co-crosslinking and ninhydrin tests were showing higher crosslinking density. Zeta potential was 47.7 to 66.2 +mV indicating the potential stability of the colloidal system. Equilibrium adsorption isotherms described encapsulated microspheres followed the Langmuir isotherm model, suggesting monolayer adsorption of the mucin on microspheres. In-vitro release studies up to four weeks indicated zero order kinetics and obeyed swelling-controlled super case II transport release mechanism. Thus, the present study could be helpful in developing the multivalent oral vaccine.

Vanillin-induced amelioration of depression-like behaviors in rats by modulating monoamine neurotransmitters in the brain

Olfaction plays an important role in emotions in our daily life. Pleasant odors are known to evoke positive emotions, inducing relaxation and calmness. The beneficial effects of vanillin on depressive model rats were investigated using a combination of behavioral assessments and neurotransmitter measurements. Before and after chronic stress condition (or olfactory bulbectomy), and at the end of vanillin or fluoxetine treatment, body weight, immobility time on the forced swimming test and sucrose consumption in the sucrose consumption test were measured. Changes in these assessments revealed the characteristic phenotypes of depression in rats. Neurotransmitters were measured using ultrahigh-performance liquid chromatography. Our results indicated that vanillin could alleviate depressive symptoms in the rat model of chronic depression via the olfactory pathway. Preliminary analysis of the monoamine neurotransmitters revealed that vanillin elevated both serotonin and dopamine levels in brain tissue. These results provide important mechanistic insights into the protective effect of vanillin against chronic depressive disorder via olfactory pathway. This suggests that vanillin may be a potential pharmacological agent for the treatment of major depressive disorder.

Identification of toxicants in cinnamon-flavored electronic cigarette refill fluids

In a prior study on electronic cigarette (EC) refill fluids, Cinnamon Ceylon was the most cytotoxic of 36 products tested. The purpose of the current study was to determine if high cytotoxicity is a general feature of cinnamon-flavored EC refill fluids and to identify the toxicant(s) in Cinnamon Ceylon. Eight cinnamon-flavored refill fluids, which were screened using the MTT assay, varied in their cytotoxicity with most being cytotoxic. Human embryonic stem cells were generally more sensitive than human adult pulmonary fibroblasts. Most products were highly volatile and produced vapors that impaired survival of cells in adjacent wells. Cinnamaldehyde (CAD), 2-methoxycinnamaldehyde (2MOCA), dipropylene glycol, and vanillin were identified in the cinnamon-flavored refill fluids using gas chromatography–mass spectrometry and high-pressure liquid chromatography (HPLC). When authentic standards of each chemical were tested using the MTT assay, only CAD and 2MOCA were highly cytotoxic. The amount of each chemical in the refill fluids was quantified using HPLC, and cytotoxicity correlated with the amount of CAD/product. Duplicate bottles of the same product were similar, but varied in their concentrations of 2MOCA. These data show that the cinnamon flavorings in refill fluids are linked to cytotoxicity, which could adversely affect EC users.

Development of drug-loaded chitosan-vanillin nanoparticles and its cytotoxicity against HT-29 cells

Chitosan as a natural polysaccharide derived from chitin of arthropods like shrimp and crab, attracts much interest due to its inherent properties, especially for application in biomedical materials. Presently, biodegradable and biocompatible chitosan nanoparticles are attractive for drug delivery. However, some physicochemical characteristics of chitosan nanoparticles still need to be further improved in practice. In this work, chitosan nanoparticles were produced by crosslinking chitosan with 3-methoxy-4-hydroxybenzaldehyde (vanillin) through a Schiff reaction. Chitosan nanoparticles were 200-250 nm in diameter with smooth surface and were negatively charged with a zeta potential of - 17.4 mV in neutral solution. Efficient drug loading and drug encapsulation were achieved using 5-fluorouracil as a model of hydrophilic drug. Drug release from the nanoparticles was constant and controllable. The in vitro cytotoxicity against HT-29 cells and cellular uptake of the chitosan nanoparticles were evaluated by methyl thiazolyl tetrazolium method, confocal laser scanning microscope and flow cytometer, respectively. The results indicate that the chitosan nanoparticles crosslinked with vanillin are a promising vehicle for the delivery of anticancer drugs.

The molecular basis for the pharmacokinetics and pharmacodynamics of curcumin and its metabolites in relation to cancer

This review addresses the oncopharmacological properties of curcumin at the molecular level. First, the interactions between curcumin and its molecular targets are addressed on the basis of curcumin's distinct chemical properties, which include H-bond donating and accepting capacity of the β-dicarbonyl moiety and the phenylic hydroxyl groups, H-bond accepting capacity of the methoxy ethers, multivalent metal and nonmetal cation binding properties, high partition coefficient, rotamerization around multiple C-C bonds, and the ability to act as a Michael acceptor. Next, the in vitro chemical stability of curcumin is elaborated in the context of its susceptibility to photochemical and chemical modification and degradation (e.g., alkaline hydrolysis). Specific modification and degradatory pathways are provided, which mainly entail radical-based intermediates, and the in vitro catabolites are identified. The implications of curcumin's (photo)chemical instability are addressed in light of pharmaceutical curcumin preparations, the use of curcumin analogues, and implementation of nanoparticulate drug delivery systems. Furthermore, the pharmacokinetics of curcumin and its most important degradation products are detailed in light of curcumin's poor bioavailability. Particular emphasis is placed on xenobiotic phase I and II metabolism as well as excretion of curcumin in the intestines (first pass), the liver (second pass), and other organs in addition to the pharmacokinetics of curcumin metabolites and their systemic clearance. Lastly, a summary is provided of the clinical pharmacodynamics of curcumin followed by a detailed account of curcumin's direct molecular targets, whereby the phenotypical/biological changes induced in cancer cells upon completion of the curcumin-triggered signaling cascade(s) are addressed in the framework of the hallmarks of cancer. The direct molecular targets include the ErbB family of receptors, protein kinase C, enzymes involved in prostaglandin synthesis, vitamin D receptor, and DNA.

Vanillin differentially affects azoxymethane-injected rat colon carcinogenesis and gene expression

Vanillin is the substance responsible for the flavor and smell of vanilla, a widely used flavoring agent. Previous studies reported that vanillin is a good antimutagen and anticarcinogen. However, there are also some contradicting findings showing that vanillin was a comutagen and cocarcinogen. This study investigated whether vanillin is an anticarcinogen or a cocarcinogen in rats induced with azoxymethane (AOM). Rats induced with AOM will develop aberrant crypt foci (ACF). AOM-challenged rats were treated with vanillin orally and intraperitoneally at low and high concentrations and ACF density, multiplicity, and distribution were observed. The gene expression of 14 colorectal cancer-related genes was also studied. Results showed that vanillin consumed orally had no effect on ACF. However, high concentrations (300 mg/kg body weight) of vanillin administered through intraperitoneal injection could increase ACF density and ACF multiplicity. ACF were mainly found in the distal colon rather than in the mid-section and proximal colon. The expression of colorectal cancer biomarkers, protooncogenes, recombinational repair, mismatch repair, and cell cycle arrest, and tumor suppressor gene expression were also affected by vanillin. Vanillin was not cocarcinogenic when consumed orally. However, it was cocarcinogenic when being administered intraperitoneally at high concentration. Hence, the use of vanillin in food should be safe but might have cocarcinogenic potential when it is used in high concentration for therapeutic purposes.

A novel multiplex polymerase chain reaction assay for profile analyses of gene expression in peripheral blood

Background

Studies have demonstrated that inflammation has a key role in the pathogenesis of atherosclerosis due to the abnormal gene expressions of multiple cytokines. We established an accurate and precise method to observe gene expression in whole blood that might provide specific diagnostic information for coronary artery disease (CAD) and other related diseases.

Methods

The fifteen selected CAD-related genes (IL1B, IL6, IL8, IFNG, MCP-1, VWF, MTHFR, SELL, TNFalpha, ubiquitin, MCSF, ICAM1, ID2, HMOX1 and LDLR) and two housekeeping genes (ACTB and GK) as internal references have been measured simultaneously with a newly developed multiplex polymerase chain reaction (multi-PCR) method. Moreover, the precision was evaluated, and a procedure for distinguishing patients from the normal population has been developed based upon analyses of peripheral blood. A total of 148 subjects were divided into group A (control group without plaques), group B (calcified plaques) and group C (non-calcified plaques, and combination group) according dual-source CT criteria. Gene expression in blood was analyzed by multi-PCR, and levels of glucose and lipids measured in 50 subjects to explore the relationship among them.

Results

The precision results of the multi-PCR system revealed within-run and between-run CV values of 3.695–12.537% and 4.405–13.405%, respectively. The profiles of cytokine gene expression in peripheral blood were set: a positive correlation between glucose and MCSF, HMOX1 or TNFalpha were found. We also found that triglyceride levels were negatively correlated with SELL gene expression in 50 subjects. Compared with controls, gene expression levels of IL1B, IL6, IL8 and MCP-1 increased significantly in group C.

Conclusions

A new multiple gene expression analysis system has been developed. The primary data suggested that gene expression was related to CAD. This system might be used for risk assessment of CVDs and other related diseases.

Carbon tetrachloride-induced nephrotoxicity and DNA damage in rats

In this study, the protective effects of vanillin were evaluated against carbon tetrachloride (CCl4)-induced kidney damages in Wistar albino rats. CCl4 (1 ml/kg, intraperitoneally [i.p.]) caused a significant induction of renal disorder, oxidative damage and DNA fragmentation as evidenced by increased plasma creatinine, urea and uric acid levels, increased lipid peroxidation (malondialdehyde [MDA]) and protein carbonyl. Furthermore, glutathione levels, catalase, superoxide dismutase, glutathione transferase and glutathione peroxidase activities were significantly decreased. A smear without ladder formation on agarose gel was also shown, indicating random DNA degradation. Pretreatment of rats with vanillin (150 mg/kg/day, i.p.), for 3 consecutive days before CCl4 injection, protected kidney against the increase of MDA and degradation of membrane proteins compared to CCl4-treated rats and exhibited marked prevention against CCl4-induced nephropathology, oxidative stress and DNA damage. Kidney histological sections showed glomerular hypertrophy and tubular dilatation in CCl4-treated rats, however, in vanillin pretreated rats, these histopathological changes were less important and present a similar structure to that of control rats. These data indicated the protective role of vanillin against CCl4-induced nephrotoxicity and suggested its significant contribution of these beneficial effects.

Effect of vanillin and ethyl vanillin on cytochrome P450 activity in vitro and in vivo

Food safety is of extreme importance to human health. Vanillin and ethyl vanillin are the widely used food additives and spices in foods, beverages, cosmetics and drugs. The objective of the present work was to evaluate the impact of vanillin and ethyl vanillin on the activities of CYP2C9, CYP2E1, CYP3A4, CYP2B6 and CYP1A2 in human liver microsomes (HLM) in vitro, and impact on the activities of CYP1A2, CYP2C, CYP3A and CYP2E1 in rat liver microsomes (RLM) in vivo. The in vitro results demonstrated that vanillin and ethyl vanillin had no significant effect on the activity of five human CYP450 enzymes with concentration ranged from 8 to 128 μM. However, after rats were orally administered vanillin or ethyl vanillin once a day for seven consecutive days, CYP2E1 activity was increased and CYP1A2 activity was decreased in RLM. The in vivo results revealed that drug interaction between vanillin/ethyl vanillin and the CYP2E1/CYP1A2-metabolizing drugs might be possible, and also suggested that the application of the above additives in foods and drugs should not be unlimited so as to avoid the adverse interaction.

Erythrocyte oxidative damage in rat treated with CCl4

Owing to the presence of hemoglobin and polyunsaturated fatty acids, erythrocytes are a convenient model to understand membrane oxidative damage induced by various xenobiotic pro-oxidants. This study investigated the antioxidant activity of vanillin, a naturally occurring food-flavoring agent, against carbon tetrachloride (CCl4)-induced erythrocyte damages in Wistar albino rats. A single injection of CCl4 (1 ml/kg, intraperitoneally [i.p.]) caused a significant induction of oxidative damage as evidenced by increased thiobarbituric acid reactive substances, protein carbonyl levels and osmotic fragility accompanied with a significant decrease in Na+/K+-ATPase and Ca2+-ATPase activities. Furthermore, catalase and superoxide dismutase activities were significantly elevated, while glutathione levels, glutathione- S-transferase and glutathione peroxidase activities were markedly reduced in the erythrocytes of CCl4-treated rats. Pretreatment of rats with vanillin (150 mg/kg/day, i.p.) for 3 consecutive days before CCl4 injection protected erythrocytes against the increase of lipid peroxidation and degradation of membrane proteins compared to CCl4-treated rats and exhibited marked prevention against CCl4-induced oxidative stress, alterations of membrane-bound enzymes as well as erythrocyte osmotic fragility. Our results suggest that vanillin plays a protective and curative role against the harmful effects of CCl4 on erythrocytes, thus ensuring membrane cell integrity.

Protective effect of vanillin against carbon tetrachloride (CCl4)-induced oxidative brain injury in rats

This study investigated the protective effects of vanillin against acute brain damage induced by carbon tetrachloride (CCl4) in rats. The study was performed on 32 male rats divided into four groups: a control group, vanillin group ([Va] 150 mg/kg/day, intraperitoneally [i.p.]) and CCl4 toxication groups received a single injection of CCl4 (1 ml/kg, i.p.; CCl4 and Va + CCl4 groups). The degree of protection in brain tissue was evaluated by the levels of malondialdehyde (MDA), glutathione (GSH), superoxide dismutase, glutathione transferase, glutathione peroxidase and nitric oxide (NO). Vanillin showed a significant brain-protective effect by decreasing the level of lipid peroxidation and NO2 and elevated the activities of antioxidative enzymes and level of GSH. Consequently vanillin blocked oxidative brain damage induced by CCl4 in rats.

Evaluation of the antioxidant, anti-inflammatory and hepatoprotective properties of vanillin in carbon tetrachloride-treated rats

The antioxidant and anti-inflammatory effects of vanillin are considered as important forces in the protection against liver injury and fibrosis. This study investigated the protective effects of vanillin against carbon tetrachoride (CCl(4))-induced hepatotoxicity in rat. Pretreatment with vanillin prior the administration of CCl(4) significantly prevented the decrease of protein synthesis and the increase in plasma alanine (ALT) and aspartate (AST) aminotransferases. Furthermore, it inhibited hepatic lipid peroxidation (MDA) and protein carbonyl (PCO) formation and attenuated the (CCl(4))-mediated depletion of antioxidant enzyme catalase and superoxide dismutase (SOD) activities and glutathione level (GSH) in the liver. In addition, vanillin markedly attenuated the expression levels of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) and prevented CCl(4)-induced hepatic cell alteration and necrosis, as indicated by liver histopathology. These findings suggest that the antioxidant and anti-inflammatory effects of vanillin against CCl(4)-induced acute liver injury may involve its ability to block CCl(4)-generated free radicals.