Fraxetin prevented sodium fluoride-induced chronic pancreatitis in rats: Role of anti-inflammatory, antioxidant, antifibrotic and anti-apoptotic activities

Simvastatin and eugenol restore autophagic flux and alleviate oxidative, inflammatory, and fibrotic perturbations in an arginine-induced chronic pancreatitis rat model

Chronic pancreatitis (CP), a progressive inflammatory disease characterized by pancreatic tissue destruction and fibrosis, is considered a challenging health burden due to insufficiencies of current management procedures. Autophagy impairment has emerged as a major triggering event in pancreatitis, raising interest in exploring the potential of targeting autophagy as a possible interventional strategy. This study aimed to evaluate the possible ameliorative effect of two autophagy modulators, simvastatin and eugenol, on CP-related perturbations in an arginine-induced rat model. Repeated l-arginine administration (5 g/kg divided into 2 doses with a 1 h interval, given intraperitoneally every 3rd day for a total of 10 times) provoked CP features, demonstrated by acinar damage, oxidative stress, inflammation, and fibrosis. Arginine-triggered pancreatitis was accompanied by hampered pancreatic autophagic flux, evidenced by overexpression of pancreatic p62 and LC3-Ⅱ and downregulation of pancreatic AMPK and LAMP-1 mRNA expression. Treatment with simvastatin (20 mg/kg, intraperitoneally 24 h, before each arginine dose) and eugenol (50 mg/kg/day orally for 30 days) achieved significant anti-oxidative, anti-inflammatory, and anti-fibrotic effects, and reversed the arginine-instigated autophagic blockade, with superior ameliorative effects attained by eugenol. Altogether, simvastatin and eugenol provide a promising interventional approach for CP, at least partly, by restoring the impaired autophagic flux associated with CP.

Dietary addition of fraxetin improved intestinal structure and growth performance in juvenile grass carp (Ctenopharyngodon idella): as a potential novel phytogenic feed additive

The well-being and development of fish are affected to varying degrees under the intensive aquaculture model, and the use of Chinese herbs for aquaculture disease control and feed additives has received increasing attention. This study examined fraxetin supplementation in juvenile grass carp to investigate its effects on growth and intestinal structure. There were 1080 grass carp (11.58 ± 0.01 g) assigned to 6 treatments, fed with fraxetin (0, 3.9, 7.9, 15.8, 31.5, and 63.1 mg/kg) for 60 days in each treatment. In our study, appropriate fraxetin significantly increased final body weight (FBW), percent weight gain (PWG), and specific growth rate (SGR) compared to the unadded group (P < 0.05), but did not affect feed efficiency (FE) (P > 0.05). The administration of 7.9 mg/kg of fraxetin significantly improved fish intestinal development and body composition. Appropriate dietary fraxetin significantly enhanced intestinal digestive enzymes and brush border enzyme activity (P < 0.05), decreased serum diamine oxidase (DAO) levels (P < 0.05), and decreased intestinal cell apoptosis (P < 0.05). Appropriate levels of fraxetin inhibited the RhoA/ROCK signaling pathway while upregulating both mRNA and protein expression of tight junction (TJ) and adherens junction (AJ) (P < 0.05). These changes significantly improved apical junction complex (AJC) integrity. In conclusion, dietary supplementation with appropriate levels of fraxetin added to the diets had a facilitating effect on digestion and absorption, improved intestinal structure, and promoted fish growth performance in juvenile grass carp. In addition, the optimal dietary fraxetin levels were evaluated to be 6.06 and 7.79 mg/kg based on linear regression analysis of PWG and DAO, respectively.

Fluoride-Induced Alterations in the Pancreas of Mammals: A Meta-analysis

This review explores the diverse effects of fluoride on pancreatic function, encompassing both in vitro and in vivo studies. Fluoride exposure induces notable alterations at the cellular and molecular levels, affecting pancreatic morphology, histology, and enzymatic activity. In vitro studies demonstrate significant inhibition of pancreatic α-amylase activity and apoptosis in pancreatic beta cells. In vivo investigations reveal structural abnormalities in pancreatic cells, including mitochondrial damage, vacuolation, and nuclear damage. Moreover, fluoride exposure disrupts antioxidant enzyme activity, exacerbating oxidative stress and lipid peroxidation. Changes in digestive enzyme activity, such as the inhibition of pancreatic lipase and α-amylase, further contribute to pancreatic dysfunction. Additionally, alterations in hormone secretion, notably insulin levels and disturbed glucose homeostasis, highlight the complex effects of fluoride on the pancreatic endocrine system. These findings underscore fluoride-induced pancreatic toxicity and highlight the need for a comprehensive understanding and mitigation strategies to safeguard pancreatic health.

Exploring fluoride's role in diabetes development: A review

PURPOSE

The element fluorine, which is never found in nature in a free state, is the source of the fluoride ion. When fluoride intake is excessive, it can cause various impairments in living organism. This review aims to assess the relationship between fluoride exposure and glucose metabolism, considering positive, negative, and null findings, with a focus on its potential role in insulin resistance and diabetes-related complications.

METHODS

Numerous studies that have demonstrated changes in blood glucose and insulin variations due to fluoride are included in our analysis on the bases of their relevance. Twenty significant research papers from Pubmed, Google Scholar, and Research Gate are included up to January 2025 using search terms such as "Fluoride," "Toxicity," "Diabetes," "Insulin resistance," "fluoride and diabetes," "fluoride and insulin," "fluoride and blood glucose" in this review. Of the 20 research papers, 14 involve normal organisms unaffected by diabetes or complications connected to the disease, serving as standard animal models, while 5 involve animals exposed to diabetes and 1 is a human population study.

RESULTS

The findings suggest a negative association between fluoride exposure and diabetes, as studies indicate fluoride's potential role in impairing glucose homeostasis and increasing insulin resistance. These research studies showed how fluoride affected the participants' blood sugar and diabetes-related complications.

CONCLUSION

This study highlights how important it is to comprehend how fluoride may contribute to diabetes or diabetes-related complications, and it makes recommendations for future research directions that might lead to the discovery of efficient treatment measures to avoid them.

Chemical proteomic profiling reveals prostaglandin termination enzyme PTGR2 as a key molecular target of natural coumarin fraxetin

Natural coumarins represent a diverse group of secondary metabolites with a wide range of biological activities. However, their specific molecular targets have remained largely unexplored. Employing chemical proteomics, a comprehensive analysis of the protein targets of the natural coumarin fraxetin has been conducted. Prostaglandin reductase 2 (PTGR2), a key enzyme involved in the final inactivation of prostaglandins, was identified as a primary target of fraxetin. Inhibition of PTGR2 can lead to the accumulation of 15-keto-PGE2, which subsequently activates the Nrf2 signaling pathway and suppresses NF-κB, resulting in notable anti-inflammatory effects. These findings provide novel insights into the molecular targets of fraxetin and other coumarins, which are crucial for fully exploring their therapeutic potential.

Fluoride-induced hypertension by regulating RhoA/ROCK pathway and phenotypic transformation of vascular smooth muscle cells: In vitro and in vivo evidence

Fluoride exposure has been implicated as a potential risk factor for hypertension, but the underlying mechanisms remain unclear. This study investigated the role of the RhoA/ROCK signaling pathway in fluoride-induced hypertension. Male Wistar rats were divided into different groups and exposed to varying concentrations of sodium fluoride (NaF) or sodium chloride (NaCl) via drinking water. The rats' blood pressure was measured, and their aortic tissue was utilized for high-throughput sequencing analysis. Additionally, rat and A7r5 cell models were established using NaF and/or Fasudil. The study evaluated the effects of fluoride exposure on blood pressure, pathological changes in the aorta, as well as the protein/mRNA expression levels of phenotypic transformation indicators (a-SMA, calp, OPN) in vascular smooth muscle cells (VSMCs), along with the RhoA/ROCK signaling pathway (RhoA, ROCK1, ROCK2, MLC/p-MLC). The results demonstrated that fluoride exposure in rats led to increased blood pressure. High-throughput sequencing analysis revealed differential gene expression associated with vascular smooth muscle contraction, with the RhoA/ROCK signaling pathway emerging as a key regulator. Pathological changes in the rat aorta, such as elastic membrane rupture and collagen fiber deposition, were observed following NaF exposure. However, fasudil, a ROCK inhibitor, mitigated these pathological changes. Both in vitro and in vivo models confirmed the activation of the RhoA/ROCK signaling pathway and the phenotypic transformation of VSMCs from a contractile to a synthetic state upon fluoride exposure. Fasudil effectively inhibited the activities of ROCK1 and ROCK2 and attenuated the phenotypic transformation of VSMCs. In conclusion, fluoride has the potential to induce hypertension through the activation of the RhoA/ROCK signaling pathway and phenotypic changes in vascular smooth muscle cells. These results provide new insights into the mechanism of fluoride-induced hypertension.

Health benefits of fraxetin: From chemistry to medicine

Fraxetin is a bioactive molecule present in various natural plants, especially Cortex Fraxini. Evidenced outcomes in phytochemical and biological analyses for this agent are now available in the literature, but an insightful review is yet unknown. The goal of the current research is to offer a panoramic illustration of natural observation, biosynthesis, synthesis, pharmacology, and pharmacokinetics for fraxetin. Esculetin and ferulic acid acted as precursors in the enzymatic biosynthetic route, whereas fraxetin could be easily synthesized from simple phenols. A great deal of interest was obtained in using this molecule for pharmacological targets. Herein, its pharmacological value included anticancer, antioxidative, anti-inflammatory, antidiabetic, antiobesity, and antimicrobial activities, as well as the protection of the liver, neurons, heart, bone, lung, kidney, and others. Anticancer activity may involve the inhibition of proliferation, invasion, and migration, together with apoptotic induction. Health benefits from this molecule were deduced from its ability to suppress cytokines and protect the immune syndrome. Various signaling pathways, such as Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3), phosphoinositide 3 kinase (PI3K)/protein kinase B (Akt), nuclear factor kappa B (NF-κB)/NLRP3, Akt/AMPK, have been proposed for in vitro and in vivo mechanisms of action. Fraxetin is highly distributed to rat plasma and several organs. However, more pharmacokinetic studies to improve its bioavailability are needed since its solubility in water is still limited.

The effects of fraxetin and monnieriside A on Cultured L929 fibroblasts

Skin lesions are considered a public health problem, compromising patients' quality of life. This work aimed to evaluate the effects of fraxetin and monnieriside A on Cultured L929 Fibroblasts through the scratch assay. Supernatants and cells from the fibroblast culture treated with the compounds were used to evaluate essential markers of the tissue repair process (IGF-1, VEGF, IL-8, IL-10, FGF-2, COL1A2, COL4A, PDGF) using ELISA and qRT-PCR. The results showed that fraxetin and MOA were non-cytotoxic and could stimulate cellular migration. Fraxetin induced IGF-1, VEGF, IL-8, and IL-10 expression, while MOA induced FGF2, COL1A2, and IL-10 expression. Altogether, these results set provides evidence that fraxetin and MOA have healing potential for tissue repair, paving the way for in vivo studies and clinical trials to validate the in vitro results.

Designing and preparing supramolecular encapsulation systems based on fraxetin and cyclodextrins for highly selective detection of nicotine

Herein, a series of water-soluble supramolecular inclusion complexes (ICs) probes were prepared using cyclodextrins (CDs) and fraxetin (FRA) to detect nicotine (NT) with high selectivity in vitro and in vivo. The FRA/CD ICs prepared through the saturated solution method exhibited excellent water solubility, stability, and biocompatibility. A clear host-guest inclusion model was provided by the theoretical calculations. The investigation revealed that NT was able to enter into the cavities of FRA/β-CD IC and FRA/γ-CD IC, and further formed charge transfer complexes with FRA in the CD cavities, resulting in a rapid and highly selective fluorescence-enhanced response with the lowest detection limits of 1.9 × 10-6 M and 9.7 × 10-7 M, and the linear response ranged from 0.02 to 0.3 mM and 0.01-0.05 mM, respectively. The IC probes showed good anti-interference performance to common interferents or different pH environments, with satisfactory reproducibility and repeatability of response to NT. Furthermore, the potentiality of the probes was confirmed through fluorescence imaging experiments using human lung cancer cells and the lung tissue of mice. This study offers a fresh perspective for detecting NT in environmental and biomedical analysis.

Fermented Rooibos tea (Aspalathus linearis) Ameliorates Sodium Fluoride-Induced Cardiorenal Toxicity, Oxidative Stress, and Inflammation via Modulation of NF-κB/IκB/IκKB Signaling Pathway in Wistar Rats

High dose of fluoride intake is associated with toxic effects on kidney and cardiac tissues. This study evaluated the potential protective effect of fermented rooibos tea (RTE) on sodium fluoride (NaF)-induced cardiorenal toxicity in rats. Male Wistar rats (n = 56) were randomly allocated into one of seven equal groups: control, NaF (100 mg/kg orally), NaF + RTE (2%, w/v), NaF + RTE (4%, w/v), NaF + lisinopril (10 mg/kg orally), 2% RTE, and 4% RTE. The experiment lasted for 14 days and RTE was administered to the rats as their sole source of drinking fluid. NaF induced cardiorenal toxicity indicated by elevated level of urea, creatinine, LDH, creatinine kinase-MB, and cardiac troponin I in the serum, accompanied by altered histopathology of the kidney and heart. Furthermore, levels of H2O2, malondialdehyde, and NO were elevated, while GSH level was depleted in the kidney and heart due to NaF intoxication. Protein levels of c-reactive protein, TNFα, IL-1B, and NF-κB were increased by NaF in the serum, kidney, and heart. RTE at 2% and 4% (w/v) reversed cardiorenal toxicity, resolved histopathological impairment, attenuated oxidative stress and inhibited formation of pro-inflammatory markers. RTE at both concentrations down-regulates the mRNA expression of NF-κB, and upregulates the mRNA expression of both IκB and IκKB, thus blocking the activation of NF-κB signaling pathway. Taken together, these results clearly suggest that the protective potential of rooibos tea against NaF-induced cardiorenal toxicity, oxidative stress, and inflammation may be associated with the modulation of the NF-κB signaling pathway.

Chemical Characterisation, Antidiabetic, Antibacterial, and In Silico Studies for Different Extracts of Haloxylon stocksii (Boiss.) Benth: A Promising Halophyte

The objective of the study is to evaluate the chemical characterisation, and biological and in silico potential of Haloxylon stocksii (Boiss.) Benth, an important halophyte commonly used in traditional medicine. The research focuses on the roots and aerial parts of the plant and extracts them using two solvents: methanol and dichloromethane. Chemical characterisation of the extracts was carried out using total phenolic contents quantification, GC-MS analysis, and LC-MS screening. The results exhibited that the aerial parts of the plant have significantly higher total phenolic content than the roots. The GC-MS and LC-MS analysis of the plant extracts revealed the identification of 18 bioactive compounds in each. The biological evaluation was performed using antioxidant, antibacterial, and in vitro antidiabetic assays. The results exhibited that the aerial parts of the plant have higher antioxidant and in vitro antidiabetic activity than the roots. Additionally, the aerial parts of the plant were most effective against Gram-positive bacteria. Molecular docking was done to evaluate the binding affinity (BA) of the bioactive compounds characterised by GC-MS with diabetic enzymes used in the in vitro assay. The results showed that the BA of γ-sitosterol was better than that of acarbose, which is used as a standard in the in vitro assay. Overall, this study suggests that the extract from aerial parts of H. stocksii using methanol as a solvent have better potential as a new medicinal plant and can provide a new aspect to develop more potent medications. The research findings contribute to the scientific data of the medicinal properties of Haloxylon stocksii and provide a basis for further evaluation of its potential as a natural remedy.

Quercetin potentiates the hepatoprotective effect of sildenafil and/or pentoxifylline against intrahepatic cholestasis: Role of Nrf2/ARE, TLR4/NF-κB, and NLRP3/IL-1β signaling pathways

AIM

Intrahepatic cholestasis is a common pathological condition of several types of liver disorders. In this study, we aimed to investigate the regulatory effects of quercetin (QU) on selected phosphodiesterase inhibitors against alpha-naphthyl isothiocyanate (ANIT)-induced acute intrahepatic cholestasis.

METHODS

Cholestasis was induced in Wistar albino rats by ANIT as a single dose (60 mg/kg; P·O.). QU (50 mg/kg, daily, P·O.), sildenafil (Sild; 10 mg/kg, twice daily, P·O.), and pentoxifylline (PTX; 50 mg/kg, daily, P.O.) were evaluated either alone or in combinations for 10 days for their antioxidant, anti-inflammatory, and anti-pyroptotic effects.

RESULTS

ANIT produced a prominent intrahepatic cholestasis as evidenced by a significant alteration in liver functions, histological structure, inflammatory response, and oxidative stress biomarkers. Furthermore, up-regulation of NF-κB-p65, TLR4, NLRP3, cleaved caspase-1, IKK-β, and IL-1β concurrently with down-regulation of Nrf-2, HO-1, and PPAR-γ expressions were observed after ANIT. QU, Sild, or PTX treatment significantly alleviated the disturbance induced by ANIT. These findings were further supported by the improvement in histopathological features. Additionally, co-administration of QU with Sild or PTX significantly improved liver defects due to ANIT as compared to the individual drugs.

SIGNIFICANCE

Combined QU with Sild or PTX exhibited promising hepatoprotective effects and anti-cholestatic properties through modulation of Nrf2/ARE, TLR4/NF- κB, and NLRP3/IL-1β signaling pathways.

An in-silico investigation of fluoride ions impact on pancreatic lipase

Fluorine is a halogen beneficial to teeth and bones at a lower concentration. But in excess, it is a toxin and causes adverse effects. Fluoride is toxic to enzymes generally when it inhibits the enzyme activity involved in metabolic pathways. Here we study invitro and invivo findings on the interaction of fluoride on the enzymes Aconitase, Adenylyl cyclase, Arginase, Cytochrome-c-oxidase, Glucose-6-phosphatase, Protein phosphatase, Succinate dehydrogenase from liver and lipase from pancreas by using molecular docking and simulations to gain insights into the mechanism by which fluoride modifies the activity of pancreatic lipase. our molecular modeling and docking studies identified that lipase is the most strongly inhibited enzyme compared to other enzymes mentioned above with -0.42 Kcal/mol binding energy and 495.78 milli molar of predicted IC50 value with interaction with Phe227 residue. To further validate this, we have taken the lipase enzyme in presence of fluoride ions for molecular dynamic simulations of 100 ns. To analyze the impact of fluoride ions on the lipase dynamics, two different simulations of 100 ns each were performed. In one simulation, we have simulated lipase in its apo form in the aqueous environment without any fluoride ions and in another simulation lipase in its apo form was kept in the presence of randomly placed fluoride ions countered with sodium ions to maintain the pH as neutral. The simulation analysis revealed that major fluctuations in lipase was observed between 230 and 300 residues in presence of fluoride ions. Interestingly, this is the exact location of the "lid" like acting loop of residues responsible for the inward/outward movement of the substrate to lipase catalytically active site containing catalytic triad of residues Leu153, His263, and Pro177. His263 residue random flip is believed to be the critical incident that causes the substrate's inward/outward movement at the catalytically active site coordinated by "lid" opening, providing enough space for the substrate.

Molecular Diversity and Biochemical Content in Two Invasive Alien Species: Looking for Chemical Similarities and Bioactivities

The biochemical composition, molecular diversity, and two different bioactivities of Asparagopsis armata and Rugulopteryx okamurae (two alien species with different invasive patterns in the southern Iberian Peninsula) were analyzed through spectrophotometric methods and Fourier transform ion cyclotron mass spectroscopy (FT-ICR-MS). A total of 3042 molecular formulas were identified from the different extracts. The dH2O extracts were the most molecularly different. A. armata presented the highest content of nitrogenous compounds (proteins, CHON) and sulphur content, whereas R. okamurae was rich in carbonated compounds (total carbon, lipids, CHO, and CHOP). Antioxidant capacity and phenolic content were higher in R. okamurae than in A. armata. Antimicrobial activity was detected from both species. A. armata showed capacity to inhibit human and fish pathogens (e.g., Staphylococcus aureus or Vibrio anguillarum), whereas R. okamurae only showed inhibition against human bacteria (Staphylococcus aureus and Cutibacterium acnes). In R. okamurae, molecules with a great number of pharmaceutical activities (e.g., anti-inflammatory or antitumoral), antibacterial, biomaterial, and other utilities were found. The main molecules of A. armata had also pharmaceutical applications (e.g., antimalarian, antithrombotic, anti-inflammatory, or antiarthritis). The valorization of these species can help to counteract the environmental effects of the bioinvasions.

Redox and biometal status in Wistar rats after subacute exposure to fluoride and selenium counter-effects

This study aimed to investigate the effect of 150 mg/L sodium fluoride (NaF) on redox status parameters and essential metals [copper (Cu), iron (Fe), and zinc (Zn)] in the blood, liver, kidney, brain, and spleen of Wistar rats and to determine the protective potential of selenium (Se) against fluoride (F^-) toxicity. Male Wistar rats were randomly distributed in groups of five (n=5) receiving tap water (control) or water with NaF 150 mg/L, NaF 150 mg/L + Se 1.5 mg/L, and Se 1.5 mg/L solutions ad libitum for 28 days. Fluorides caused an imbalance in the redox and biometal (Cu, Fe, and Zn) status, leading to high superoxide anion (O^{2 .-}) and malondialdehyde (MDA) levels in the blood and brain and a drop in superoxide dismutase (SOD1) activity in the liver and its increase in the brain and kidneys. Se given with NaF improved MDA, SOD1, and O^{2 .-} in the blood, brain, and kidneys, while alone it decreased SH group levels in the liver and kidney. Biometals both reduced and increased F- toxicity. Further research is needed before Se should be considered as a promising strategy for mitigating F^- toxicity.

Berberine inhibits pancreatic intraepithelial neoplasia by inhibiting glycolysis via the adenosine monophosphate -activated protein kinase pathway

Most cases of pancreatic cancer develop in patients with chronic pancreatitis (CP). Berberine is natural product that exhibits anti-tumor effects in various types of cancer and is used in traditional Chinese medicine. In this study, we demonstrated that berberine inhibited the development of pancreatic intraepithelial neoplasia (PanIN) in an in vivo CP model and an in vitro acinar-to-ductal metaplasia model. As berberine may inhibit glycolysis during the development of PanIN, we measured indicators of glycolysis. Quantitative reverse transcription polymerase chain reaction and western blotting assays revealed that berberine activated the adenosine monophosphate-activated protein kinase (AMPK) pathway. This demonstrated that berberine suppressed glycolysis by targeting AMPK, a key metabolic sensor. Furthermore, berberine acted via the AMPK-hypoxia-inducible factor 1 alpha pathway to achieve suppression of PanIN. These findings show that berberine is a potential therapeutic candidate for preventing the progression of CP to PanIN.