Scopoletin Research Articles

Scopoletin and rutin attenuate ethanol reward in mouse-conditioned place preference test

IntroductionIn Traditional Chinese Medicine (TCM), Morinda citrifolia Linn. (Hai ba ji), is utilized for its various parts such as leaves, fruits, flowers, roots, and bark, serving as a tonic and addressing ailments including fever, skin, eye, throat, and gum issues, as well as nausea, vomiting, and neurological diseases. Previous research indicated that M. citrifolia Linn. fruit and its juice reduced ethanol-conditioned place preference (CPP) in mice, with scopoletin (SCOP) and rutin (RUT) proposed as the main bioactive compounds responsible for this effect. This study aimed to evaluate the impact of SCOP and RUT on ethanol reward using the CPP test in mice. MethodsThe CPP protocol consisted of a habituation phase spanning 3 days, a 1-day preconditioning phase, 10 days of conditioning, a rest day, and a post-conditioning day. The vehicle-saline control and vehicle-ethanol control groups received oral administration of a 1 % w/v solution of sodium carboxymethyl cellulose (CMC) at a dosage of 10 ml/kg. SCOP and RUT were administered orally at doses ranging from 0.05 to 1 mg/kg body weight (bw), while acamprosate (ACAM) was administered at a dosage of 300 mg/kg bw, all one hour before postconditioning. Statistical analyses utilized both repeated measures two-way and one-way ANOVA. ResultsOral administration of SCOP (0.05, 0.1, and 0.5 mg/kg bw) and RUT (0.05 mg/kg bw) one hour before postconditioning testing on day 16 markedly reduced ethanol CPP in mice. Additionally, SCOP and RUT at all tested doses (0.05–1 mg/kg bw, p.o.) did not induce any changes in normal locomotor activity in mice. DiscussionThese results suggest that SCOP and RUT diminish ethanol reward in mice, underscoring the therapeutic potential of these phytochemicals in managing alcohol use disorder.

Scopoletin alleviates high glucose-induced toxicity in human renal proximal tubular cells via inhibition of oxidative damage, epithelial-mesenchymal transition, and fibrogenesis.

Recent years of evidence suggest the crucial role of renal tubular cells in developing diabetic kidney disease. Scopoletin (SCOP) is a plant-based coumarin with numerous biological activities. This study aimed to determine the effect of SCOP on renal tubular cells in developing diabetic kidney disease and to elucidate mechanisms. In this study, SCOP was evaluated in vitro using renal proximal tubular (HK-2) cells under hyperglycemic conditions to understand its mechanism of action. In HK-2 cells, SCOP alleviated the high glucose-generated reactive oxygen species (ROS), restored the levels of reduced glutathione, and decreased lipid peroxidation. High glucose-induced alteration in the mitochondrial membrane potential was markedly restored in the SCOP-treated cells. Moreover, SCOP significantly reduced the high glucose-induced apoptotic cell population in the Annexin V-FITC flow cytometry study. Furthermore, high glucose markedly elevated the mRNA expression of fibrotic and extracellular matrix (ECM) components, namely, transforming growth factor (TGF)-β, alfa-smooth muscle actin (α-SMA), collagen I, and collagen III, in HK-2 cells compared to the untreated cells. SCOP treatment reduced these mRNA expressions compared to the high glucose-treated cells. Collagen I and TGF-β protein levels were also significantly reduced in the SCOP-treated cells. Further findings in HK-2 cells revealed that SCOP interfered with the epithelial-mesenchymal transition (EMT) in the high glucose-treated HK-2 cells by normalizing E-cadherin and downregulating the vimentin and α-SMA proteins. In conclusion, SCOP modulates the high glucose-generated renal tubular cell oxidative damage and accumulation of ECM components and may be a promising molecule against diabetic nephropathy.

A 7-Hydroxy 4-Methylcoumarin Enhances Melanogenesis in B16-F10 Melanoma Cells.

The objectives of this study were to investigate the melanogenetic potentials of the naturally occurring 7-hydroxy coumarin derivatives 7-hydroxy 5,6-dimethoxycoumarin (7H-5,6DM), 7-hydroxy 6,8-dimethoxycoumarin (7H-6,8DM), 7-hydroxy 6-methoxycoumarin (7H-6M), and 7-hydroxy 4-methylcoumarin (7H-4M) in the melanogenic cells model for murine B16F10 melanoma cells. The initial results indicated that melanin production and intracellular tyrosinase activity were significantly stimulated by 7H-4M but not by 7H-5,6DM, 7H-6,8DM, or 7H-6M. Therefore, our present study further investigated the melanogenic effects of 7H-4M in B16-F10 cells, as well as its mechanisms of action. In a concentration-dependent manner, 7H-4M increased intracellular tyrosinase activity, leading to the accumulation of melanin without affecting the viability of B16-F10 cells. Our study further investigated the effects of 7H-4M on melanogenesis, including its ability to promote tyrosinase activity, increase melanin content, and activate molecular signaling pathways. The results indicate that 7H-4M effectively stimulated tyrosinase activity and significantly increased the expression of melanin synthesis-associated proteins, such as microphthalmia-associated transcription factor (MITF), tyrosinase, tyrosinase-related protein-1 (TRP1), and TRP2. Based on our findings, we can conclude that 7H-4M has the ability to activate the melanogenesis process through the upregulation of cAMP-dependent protein kinase (PKA) and the cAMP response element-binding protein (CREB). Additionally, our study showed that 7H-4M induced melanogenic effects by downregulating the extracellular signal-regulated kinase (ERK) and the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt)/glycogen synthesis kinase-3β (GSK-3β) cascades, while upregulating the JNK and p38 signaling pathways. Finally, the potential of using 7H-4M in topical applications was tested through primary human skin irritation tests. During these tests, no adverse reactions were induced by 7H-4M. In summary, our results indicate that 7H-4M regulates melanogenesis through various signaling pathways such as GSK3β/β-catenin, AKT, PKA/CREB, and MAPK. These findings suggest that 7H-4M has the potential to prevent the development of pigmentation diseases.

Granulated organoclay as a sorbent to protect the allelochemical scopoletin from rapid biodegradation in soil

Allelochemicals have been proposed as environmentally friendly bioherbicides, but their short persistence in soils often limits their performance as natural weed management products. In this study, incorporation into organoclay granules was investigated as a strategy to protect the allelochemical scopoletin from rapid biodegradation and prolong its persistence in soil. The commercial organoclay Cloisite® 10A, in its raw powder form, was used to prepare the granules. A kinetic study revealed slower sorption of scopoletin on the granules than on the organoclay powder and indicated an intraparticle pore diffusion mechanism. The half-life of scopoletin in soil under laboratory conditions increased significantly by incorporating the allelochemical into the organoclay granules, from 0.34 to 14.4 days. A field experiment was also conducted to assess whether the increase in soil half-life measured under controlled laboratory conditions translated to field conditions and to compare the phytotoxicity of the granulated allelochemical with that of its free (dissolved) form. The addition of scopoletin-loaded organoclay granules to soil plots rendered a field half-life for the allelochemical of 20.1 d, in contrast to the value of 0.54 d obtained for its free form. The granules also favored the expression of the phytotoxicity of scopoletin, reducing germination and root growth of Lactuca sativa L. to a greater extent than free scopoletin. The results of this work indicate that incorporation into organoclay granules could be a suitable technological approach to provide allelochemicals with protection from rapid biodegradation losses in soil, which may help increase their persistence for a better performance as crop protection products. • Organoclay granules were assayed as sorbents of the allelochemical scopoletin (SCP). • Intraparticle pore diffusion governed SCP sorption on the granules. • Sorption on the granules provided SCP with protection from rapid biodegradation. • The granules increased SCP soil persistence under laboratory and field conditions. • The increase in soil persistence of SCP favored the expression of its phytotoxicity.

Multi-component pharmacokinetics assessment of Artemisia annua L. in rats based on LC-ESI-MS/MS quantification combined with molecular docking

Artemisia annua L. ( A. annua ) has been used as herbal medicine in China for thousands of years for clearing deficiency heat, treating malaria and removing jaundice. A rapid, sensitive and specific liquid chromatography coupled with electrospray ionization tandem mass spectrometry (LC–ESI–MS/MS) method was developed, validated, and successfully used for simultaneous quantification of the active components in rat plasma after oral administration of A. annua extract. Molecular docking of each component with drug metabolizing enzymes was carried out to explore the effect of each component on CYP-mediated drug metabolism. Two coumarins (scopolin (SPL) and scopoletin (SPLT)), three flavonoids (rutin (RUT), chrysosplenol D (CHD), casticin (CAS)) and three sesquiterpenes (arteannuin B (ARN), dihydroartemisinic acid (DARM) and artemisinic acid (ARM)) were detected in rat plasma after oral administration. CHD and CAS were rapidly absorbed into rat blood with the T max values of 0.11 ± 0.04 h and 0.13 ± 0.05 h, respectively. Their half-lives (t 1/2 2.68 ± 3.62 h and 0.33 ± 0.07 h) were shorter. SPLT were also rapidly absorbed into the blood (T max 0.15 ± 0.03 h), but exhibited a longer half-life (t 1/2 6.53 ± 1.84 h), indicating that it could be effective in vivo for a longer period of time. The peak time of SPL, RUT, DARM and ARM ranged from 1 ∼ 4 h, demonstrating that they could maintain considerable concentrations for a longer time. ARN showed strong enterohepatic circulation in rats, leading to slower onset time and longer effect. A few components including SPLT, CHD, CAS and ARN could be metabolized into their corresponding II phase metabolites combining with glucuronic acid or sulfuric acid. RUT could decompose its glycosyl to generate genin. The molecular docking results indicated that those flavonoids and coumarins of A. annua interacting with CYPs mainly through hydrogen bonding and π-π stacking had better CYP450 enzyme binding ability than the sesquiterpenoids, which were easier to induce drug interactions. This study presented an integrated strategy for investigating the pharmacokinetic behaviors of eight components in A. annua and laid the foundation for revealing the mechanism of action of A. annua in the organism.

An insight into polyscopoletin electrosynthesis by a quality-by-design approach

Scopoletin (SP) as a functional monomer for electropolymerization has recently been investigated in the context of molecularly imprinted polymers for biosensing applications. Herein we describe an in-depth analysis of the mechanisms involved in the electropolymerization of SP toward the optimization of the experimental conditions for applications in sensor studies. PolySP films have been in situ synthesized on a standard glassy carbon electrodes by varying three independent experimental parameters, and the output of the analysis has been evaluated in terms of the resulting electroactive area and surface coverage. A quality-by-design approach including design-of-experiments principles and response surface methodology produced unbiased observations on the most relevant parameters to be controlled during the electropolymerization of SP. By combining the output of electroactive area and surface overage, we highlighted a strong dependence on the monomer concentration and scan rate. Thus, an appropriate selection of these two parameters should be sought to have an optimal electropolymerization process, leading to uniform films and homogeneous surface behavior. This study shows that the application of multi-factorial analysis in a comprehensive design of experiments allows the systematic study of polymer electrosynthesis. Therefore, this research is expected to guide further efforts in the electropolymerization of several functional monomers.

Retrieving the in vivo Scopoletin Fluorescence Excitation Band Allows the Non-invasive Investigation of the Plant-Pathogen Early Events in Tobacco Leaves.

In this study, we developed and applied a new spectroscopic fluorescence method for the in vivo detection of the early events in the interaction between tobacco (Nicotiana tabacum L.) plants and pathogenic bacteria. The leaf disks were infiltrated with a bacterial suspension in sterile physiological solution (SPS), or with SPS alone as control. The virulent Pseudomonas syringae pv. tabaci strain ATCC 11528, its non-pathogenic ΔhrpA mutant, and the avirulent P. syringae pv. tomato strain DC3000 were used. At different post-infiltration time–points, the in vivo fluorescence spectra on leaf disks were acquired by a fiber bundle-spectrofluorimeter. The excitation spectra of the leaf blue emission at 460 nm, which is mainly due to the accumulation of coumarins following a bacterial infiltration, were processed by using a two-bands Gaussian fitting that enabled us to isolate the scopoletin (SCT) contribution. The pH-dependent fluorescence of SCT and scopolin (SCL), as determined by in vitro data and their intracellular localization, as determined by confocal microscopy, suggested the use of the longer wavelength excitation band at 385 nm of 460 nm emission (F385_460) to follow the metabolic evolution of SCT during the plant–bacteria interaction. It was found to be directly correlated (R2 = 0.84) to the leaf SCT content, but not to that of SCL, determined by HPLC analysis. The technique applied to the time-course monitoring of the bacteria–plant interaction clearly showed that the amount and the timing of SCT accumulation, estimated by F385_460, was correlated with the resistance to the pathogen. As expected, this host defense response was delayed after P. syringae pv. tabaci ATCC 11528 infiltration, in comparison to P. syringae pv. tomato DC3000. Furthermore, no significant increase of F385_460 (SCT) was observed when using the non-pathogenic ΔhrpA mutant of P. syringae pv. tabaci ATCC 11528, which lacks a functional Type Three Secretion System (TTSS). Our study showed the reliability of the developed fluorimetric method for a rapid and non-invasive monitoring of bacteria-induced first events related to the metabolite-based defense response in tobacco leaves. This technique could allow a fast selection of pathogen-resistant cultivars, as well as the on-site early diagnosis of tobacco plant diseases by using suitable fluorescence sensors.

A Novel Enzyme-Free Ratiometric Fluorescence Immunoassay Based on Silver Nanoparticles for the Detection of Dibutyl Phthalate from Environmental Waters.

A novel ratiometric fluorescent immunoassay was developed based on silver nanoparticles (AgNPs) for the sensitive determination of dibutyl phthalate (DBP). In the detection system, AgNPs were labeled on the secondary antibody (AgNPs@Ab2) for signal amplification, which aimed to regulate the H2O2 concentrations. When AgNPs-Ab2 and antigen–primary antibody (Ab1) were linked by specific recognition, the blue fluorescence of Scopoletin (SC) could be effectively quenched by the H2O2 added while the red fluorescence of Amplex Red (AR) was generated. Under the optimized conditions, the calculated detection of limit (LOD, 90% inhibition) reached 0.86 ng/mL with a wide linear range of 2.31–66.84 ng/mL, which was approximately eleven times lower than that by HRP-based traditional ELISA with the same antibody. Meanwhile, it could improve the inherent built-in rectification to the environment by the combination of the dual-output ratiometric fluorescence assays with ELISA, which also enhanced the accuracy and precision (recoveries, 87.20–106.62%; CV, 2.57–6.54%), indicating it can be applied to investigate the concentration of DBP in water samples.

Scopoletin protects retinal ganglion cells 5 from high glucose-induced injury in a cellular model of diabetic retinopathy via ROS-dependent p38 and JNK signaling cascade.

The protective activity of scopoletin (SPT) against glucose-induced cataract has been attributed to attenuation of aldose reductase activity and oxidative stress in a rat model. The present investigation was aimed to study the protective effect and mechanism of SPT in retinal ganglia cells (RGC) under oxidative stress and apoptosis induced by hyperglycemia. The RGC-5 cells were pre-conditioned with variable SPT concentrations for 6 hours and then subjected to hyperglycemia for 48 hours. The cell viability, mito- chondrial membrane potential (MMP) and oxidative stress markers were quantified. Western blotting was employed to screen the expression of mitogen-activated protein kinase (MAPK) and various apoptosis related proteins. SPT blocked the high-glucose induced cell injury and normalized the mitochondrial functioning via lowering the loss of MMP and release of cytochrome c. Pretreatment with SPT suppressed the enhanced ROS, malondialdehyde, and protein carbonyl content triggered by high-glucose exposure in RGC-5 cells. SPT normalized the apoptotic proteins in RGC-5 cells. The phosphorylation of c-Jun N-terminal kinases (JNK) and p38 MAPK in RGC-5 due to hyperglycemia was attenuated by SPT. Overall, SPT exhibited a protective effect in RGC-5 cells exposed to a high-glucose environment via its antioxidant efficacy, inhibition of apoptosis and modulation of the ROS-dependent p38/JNK signaling cascade.

Universal Nanoplatform for Ultrasensitive Ratiometric Fluorescence Detection and Highly Efficient Photothermal Inactivation of Pathogenic Bacteria.

Pathogenic bacterial contamination in diverse environments seriously threatens human health. One of the most valuable approaches is to effectively combine sensitive detection with efficient sterilization to achieve source control of pathogens. Here, we constructed a nanoplatform of Bi2S3@MnO2@Van with targeting, photothermal, and oxidase properties for the detection and on-demand inactivation of bacteria. The Bi2S3@MnO2@Van nanorods (NRs) can be trapped on the surface of Gram-positive bacteria such as Staphylococcus aureus, forming a complex of Bi2S3@MnO2@Van/S. aureus. After being centrifuged, the suspension of Bi2S3@MnO2@Van NRs can catalyze the non-fluorescent Amplex Red (AR) into a fluorescent substrate and fluorescent Scopoletin (SC) into a non-fluorescent substrate. Thus, a ratiometric fluorescent sensor was constructed for the sensitive detection of bacteria with the fluorescent intensity ratio (SC/AR) as a readout, which improves anti-interference capability and can be used in real sample detection. The detection limit reaches as low as 6.0 CFU/mL. Meanwhile, the sediment contains Bi2S3@MnO2@Van/S. aureus where the bacteria can be effectively inactivated, thanks to the excellent photothermal property of Bi2S3@MnO2@Van NRs under near-infrared irradiation. The antibacterial efficiency reaches as high as 99.1%. The investigation provides an effective way for sensitive detection and highly efficient killing of pathogenic bacteria with a universal platform.

Scopoletin and umbelliferone from Cortex Mori as protective agents in high glucose-induced mesangial cell as in vitro model of diabetic glomerulosclerosis.

Two known coumarins, scopoletin (SP) and umbelliferone (UB), were isolated from Cortex Mori (CM). Their structures were elucidated by various spectroscopic analyses. Then, their effects on rat glomerular mesangial cells (RGMCs, HBZY-1) proliferation, hypertrophy, extracellular matrix (ECM) proliferation, expression of fibronectin, transforming growth factor-beta (TGF-β), and connective tissue growth factor (CTGF) induced by high glucose were studied in vitro model of diabetic glomerulosclerosis. The results show that, CM, SP, and UB can inhibit the RGMCs proliferation to attenuate the ECM proliferation and cell hypertrophy, reduced the accumulation of ECM protein fibronectin, and lowered the expression of the key fibrosis factor TGF-β and CTGF to inhibit the kidney fibrosis and thereby improved diabetic glomerulosclerosis. The two coumarins show great potentialities on treating diabetic glomerulosclerosis, but the animal experiment and mechanism is strongly needed for further proof.

HPLC Method Validation for Quantitative Analysis of Scopoletin from Hot-Water Extract Powder of Artemisia annua Linné

HPLC Method Validation for Quantitative Analysis of Scopoletin from Hot-Water Extract Powder of Artemisia annua Linné

Scopoletin ameliorates anxiety-like behaviors in complete Freund\u2019s adjuvant-induced mouse model

Anxiety disorder is highly prevalent worldwide and represents a chronic and functionally disabling condition, with high levels of psychological stress characterized by cognitive and physiological symptoms. Scopoletin (SP), a main active compound in Angelica dahurica, is traditionally used for the treatment of headache, rhinitis, pain, and other conditions. Here, we evaluated the effects of SP in a mouse model of complete Freund’s adjuvant (CFA)-induced chronic inflammation anxiety. SP (2.0, 10.0, 50.0 mg/kg) administration for 2 weeks dose-dependently ameliorated CFA-induced anxiety-like behaviors in the open field test and elevated plus maze test. Moreover, we found that SP treatment inhibited microglia activation and decreased both peripheral and central IL-1β, IL-6, and TNF-α levels in a dose-dependent manner. Additionally, the imbalance in excitatory/inhibitory receptors and neurotransmitters in the basolateral nucleus after CFA injection was also modulated by SP administration. Our findings indicate that the inhibition of the nuclear factor-kappa B and mitogen-activated protein kinase signaling pathways involving anti-inflammatory activities and regulation of the excitatory/inhibitory balance can be attributed to the anxiolytic effects of SP. Moreover, our molecular docking analyses show that SP also has good affinity for gamma-aminobutyric acid (GABA) transaminase and GABAA receptors. Therefore, these results suggest that SP could be a candidate compound for anxiolytic therapy and for use as a structural base for developing new drugs.

Scopoletin Activates Adenosine Monophosphate-Activated Protein Kinase/Mammalian Target of Rapamycin Signaling Pathway and Improves Functional Recovery after Spinal Cord Injury in Rats

Background: Scopoletin (SPT) is known to exert neuroprotective autophagy effect. However, the efficacy of SPT in the treatment of spinal cord injury (SCI) has yet not been explored. The investigation was intended to elucidate whether SPT can exert neuroprotective effect by triggering neuronal autophagy after SCI. The study was also directed to investigate the role of adenosine monophosphate-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) signaling pathway in the autophagy facilitated by SPT. Materials and Methods: The SCI was developed in female Sprague-Dawley rats by damaging the T10 spinal level using an impounder impact. Three animals groups were investigated – Sham group, SCI group, and SCI + SPT group. The SCI + SPT group was administered with SPT (100 mg/kg) intraperitoneally. Basso, Beattie, and Bresnahan scores and angle of incline test revealed that SPT administration improved the movement of hind limbs after SCI induction. Results: Results indicated that SPT imparted neuronal protection, alleviated neuronal apoptosis, and improved neuronal autophagy. SPT-induced autophagy was identified by increased Beclin-1 expression and LC3B-positive neuronal cells. Further investigations revealed that SPT triggers the pathway involving AMPK/mTOR signaling, thereby stimulating autophagy in SCI-induced rat model. Conclusion: The findings of the present investigation strongly advocate the beneficial effects of SPT in the treatment of the SCI. SPT ameliorates the AMPK/mTOR signaling-induced autophagy and thereby improves functional recovery in SCI-induced rats.

Ratiometric fluorescence sensor for organophosphorus pesticide detection based on opposite responses of two fluorescence reagents to MnO2 nanosheets

The detection of organophosphorus pesticides (OPs) has received considerable attention for their great harm to human beings. Herein, a novel ratiometric fluorescence biosensor was constructed for the determination of OPs by using Scopoletin (SC) and Amplex Red (AR) as probe pairs that have opposite responses to MnO2 nanosheets (MnO2 NS). MnO2 NS possess peroxidase-like catalytic activity, which could quench the fluorescence of SC as well as enhance the fluorescence of the non-fluorescent substance AR by oxidation. In the absence of OPs, acetylcholinesterase (AChE) hydrolyzed acetylcholine chloride (ATCh) into choline (TCh) and acetate. TCh led the decomposition of MnO2 NS to manganese ions (Mn2+), increasing signal of SC and decreasing signal of AR. In the presence of OPs, the activity of AChE was inhibited and the decomposition of MnO2 NS was hindered, therefore the fluorescence intensity of SC was weak and the fluorescence intensity of AR had an obvious increase. Moreover, under the optimal conditions, the ratio of fluorescence intensity response recorded on the AR/SC increases with increasing the concentration of DDVP. The method has wider linear range of 5.0 pg/mL ∼500 ng/mL with a detection limit of 1.6 pg/mL, which is superior to previously reported methods. This strategy has also been applied to a visual observation based on the color change of the solution under UV light.

A hierarchical cobalt/carbon nanotube hybrid nanocomplex-based ratiometric fluorescent nanosensor for ultrasensitive detection of hydrogen peroxide and glucose in human serum.

Highly sensitive detection of H2O2 and glucose is critical for fundamental research and disease diagnosis. A ratiometric sensor can simultaneously afford two readout signals that provide an internally normalized response to change, thereby reducing false results and improving detection accuracy. A novel ratiometric fluorescent nanosensor for ultrasensitive detection of hydrogen peroxide and glucose was constructed on the basis of the peroxidase-like properties of a hierarchical cobalt/carbon nanotube hybrid nanocomplex (Co-CNT). The as-prepared Co-CNT catalyzes the transformation of the non-fluorescent Amplex Red (AR) into a fluorescent derivative and the transformation of fluorescent scopoletin (SC) into a non-fluorescent derivative in the presence of H2O2. The sensing system changes colour from yellow to blue, which can be clearly seen with the naked eye. With the fluorescence ratio of AR to SC as readout, the detection limit of H2O2 reaches as low as 100nM. The developed assay is further utilized for determining H2O2-related oxidase reactions with the glucose and glucose oxidase system as model. Glucose can be selectively and sensitively detected as low as 150nM. Satisfactory recoveries are obtained for glucose detection in serum samples. The developed assay is simple in terms of preparation and operation and provides a straightforward method for cost-effective and reliable detection of H2O2 and H2O2-related reactions in clinical diagnosis and biomedical applications. Graphical abstract.

Supplementation of scopoletin improves insulin sensitivity by attenuating the derangements of insulin signaling through AMPK.

Scopoletin (SPL), a phenolic coumarin, is reported to regulate glucose metabolism. This study is initiated to substantiate the action of SPL on the regulation of insulin signaling in insulin resistant RIN5f cells and high fat, high fructose diet (HFFD)-fed rat model. Adult male Sprague Dawley rats were fed HFFD for 45days to induce type 2 diabetes and then treated or untreated with SPL for the next 45days. The levels of glucose, insulin, lipid profile, oxidative stress markers along with insulin signaling and AMPK protein expressions were examined at the end of 90days. SPL lowered the levels of plasma glucose, insulin, and lipids which were increased in HFFD-fed rats. HFFD intake suppressed the activities of antioxidant enzymes such as superoxide dismutase, catalase, and glutathione peroxidase; however, they were reversed by SPL supplementation, which reduced TBARS, lipid hydroperoxide, and protein carbonyl levels both in plasma and pancreas. SPL supplementation significantly activated insulin receptor substrate 1 (IRS1), phosphatidyl inositol 3-kinase (PI3K), and protein kinase B (Akt) phosphorylation which was suppressed in HFFD rats due to lipotoxicity. Moreover, SPL significantly activated AMPK and enhanced the association of IRS1-PI3K-Akt compared to the control group. The results revealed that SPL alleviated T2D induced by HFFD by escalating the antioxidant levels and through insulin signaling regulation. We conclude that SPL can improve insulin signaling through AMPK, thereby confirming the role of SPL as an AMPK activator.

Protective Effect of Scopoletin Against Cerulein-Induced Acute Pancreatitis and Associated Lung Injury in Mice.

The present study aimed to evaluate the protective effects of scopoletin (SC) on cerulein-induced acute pancreatitis (AP) and associated lung injury in mice. Acute pancreatitis was induced in male Swiss mice by 6 consecutive hourly intraperitoneal injections of cerulein (50 μg/kg). Scopoletin was administered 1 hour (intraperitoneal, 10 mg/kg) after the first cerulein injection. Administration of SC attenuated the severity of AP and associated lung injury as shown by histology, reduced myeloperoxidase, and serum amylase activity. Further, the anti-inflammatory effect of SC was associated with a reduction of pancreatic and pulmonary proinflammatory cytokines (interleukin 1β and tumor necrosis factor α) and hydrogen sulfide. Moreover, SC inhibited cerulein-induced nuclear factor κB activation in both pancreas and lung. Also, SC treatment further enhances the beneficial effect by reducing cerulein-induced mast cell activation as shown by reduced monocyte chemoattractant protein 1, interleukin 33, and preprotachykinin A expression (encodes neuropeptide substance P) in the pancreas and lungs. The present findings show for the first time that in AP SC may exhibit an anti-inflammatory effect by down-regulating substance P and hydrogen sulfide signaling via nuclear factor κB pathway.

Effect of scopoletin on fascia-wrapped diced cartilage grafts

Purpose: To evaluate the effect of scopoletin (SL) on fascia-wrapped diced cartilage grafts in rhinoplasty surgery.Methods: Cartilage grafts (2 × 2 cm) from the ears of New Zealand rabbits were diced into sections (1 mm3) and then wrapped in muscle fascia taken from the right rear leg. Each graft was placed on the back of the animal after measuring its weight, and then the rabbits were separated into two groups, viz, control and the SL-treated groups {10 mg/kg, per os (p.o.)}. The treatments were administered for 3 months, the rabbits were sacrificed, and the histopathological features and weight of the grafts were examined.Results: The weight of the grafts in the two groups did not significantly (p < 0.05) differ but the histopathological results suggested that there was a pronounced increase in the viability of the graft tissues in the SL-treated group compared to the control group. Treatment with SL decreased the resorption rate and enhanced basophilia relative to the control group. However, fibrosis, inflammation, and bone metaplasia- and calcification-like factors did not significantly differ (p < 0.05).Conclusion: Treatment with SL significantly enhances the viability of the grafts, and thus may have a beneficial effect on fascia-wrapped diced cartilage grafts.Keywords: Scopoletin, Rhinoplasty surgery, Fascia-wrapped diced cartilage graft, Histopathology, Basophilia, Inflammation

Introducing Ratiometric Fluorescence to MnO2 Nanosheet-Based Biosensing: A Simple, Label-Free Ratiometric Fluorescent Sensor Programmed by Cascade Logic Circuit for Ultrasensitive GSH Detection.

Glutathione (GSH) plays crucial roles in various biological functions, the level alterations of which have been linked to varieties of diseases. Herein, we for the first time expanded the application of oxidase-like property of MnO2 nanosheet (MnO2 NS) to fluorescent substrates of peroxidase. Different from previously reported fluorescent quenching phenomena, we found that MnO2 NS could not only largely quench the fluorescence of highly fluorescent Scopoletin (SC) but also surprisingly enhance that of nonfluorescent Amplex Red (AR) via oxidation reaction. If MnO2 NS is premixed with GSH, it will be reduced to Mn2+ and lose the oxidase-like property, accompanied by subsequent increase in SC's fluorescence and decrease in AR's. On the basis of the above mechanism, we construct the first MnO2 NS-based ratiometric fluorescent sensor for ultrasensitive and selective detection of GSH. Notably, this ratiometric sensor is programmed by the cascade logic circuit (an INHIBIT gate cascade with a 1 to 2 decoder). And a linear relationship between ratiometric fluorescent intensities of the two substrates and logarithmic values of GSH's concentrations is obtained. The detection limit of GSH is as low as 6.7 nM, which is much lower than previous ratiometric fluorescent sensors, and the lowest MnO2 NS-based fluorescent GSH sensor reported so far. Furthermore, this sensor is simple, label-free, and low-cost; it also presents excellent applicability in human serum samples.