Harmine induced apoptosis in Spodoptera frugiperda Sf9 cells by activating the endogenous apoptotic pathways and inhibiting DNA topoisomerase I activity

Nonlinear transcriptomic responses to compounded environmental changes across temperature and resources in a pest beetle, Callosobruchus maculatus (Coleoptera: Chrysomelidae)

Many species are experiencing drastic and multidimensional changes to their environment due to anthropogenic events. These multidimensional changes may act nonadditively on physiological and life history responses, and thus may not be predicted by responses to single dimensional environmental changes. Therefore, work is needed to understand species' responses to multiple aspects of change. We used whole-transcriptomic RNA-Sequencing and life history assays to uncover responses to singly-applied shifts in resource or temperature environmental dimensions, in comparison to combined, multidimensional change, in the crop pest seed beetle, Callosobruchus maculatus. We found that multidimensional change caused larger fecundity, developmental period and offspring viability life history changes than predicted by additive effects of 1-dimensional changes. In addition, there was little overlap between genes differentially expressed under multidimensional treatment versus under altered resource or temperature conditions alone. Moreover, 115 genes exhibited significant resource × temperature interaction effects on expression, including those involved in energy metabolism, detoxification, and enhanced formation of cuticle structural components. We conclude that single dimensional changes alone cannot determine life history and transcriptomic responses to multidimensional environmental change. These results highlight the importance of studying multidimensional environmental change for understanding the molecular and phenotypic responses that may allow organisms including insects to rapidly adapt simultaneously to multiple aspects of environmental change.

Exposure to Sublethal Concentrations of Dinotefuran Induces Apoptosis in the Gut of Diaphorina citri Adults via Activating the Mitochondrial Apoptotic Pathway

Diaphorina citri is a serious citrus pest. Dinotefuran is highly insecticidal against D. citri. To analyze the sublethal effects of dinotefuran on D. citri adults, an indoor toxicity test was performed, which revealed that the lethal concentration 50 (LC50) values were 4.23 and 0.50 μg/mL for 24 and 48 h treatments, respectively. RNA-Seq led to the identification of 71 and 231 differentially expressed genes (DEGs) after dinotefuran treatments with LC20 and LC50 doses, respectively. Many of the DEGs are significantly enriched in the apoptosis pathway. Dinotefuran-induced apoptosis in the gut cells was confirmed through independent assays of 4',6-diamidino-2-phenylindole (DAPI) and TdT-mediated dUTP nick end labeling (TUNEL) staining. Increased levels of reactive oxygen species (ROS) and a loss of mitochondrial membrane potential were observed. Four caspase genes were identified, and dinotefuran treatments resulted in increased mRNA levels of DcCasp1 and DcCasp3a. These findings shed light on the sublethal effects of dinotefuran on D. citri.

Evaluation of the Therapeutic Effects of Harmine on Anaplastic Thyroid Cancer Cells

Anaplastic thyroid carcinoma (ATC) is an extremely difficult disease to tackle, with an overall patient survival of only a few months. The currently used therapeutic drugs, such as kinase inhibitors or immune checkpoint inhibitors, can prolong patient survival but fail to eradicate the tumor. In addition, the onset of drug resistance and adverse side-effects over time drastically reduce the chances of treatment. We recently showed that Twist1, a transcription factor involved in the epithelial mesenchymal transition (EMT), was strongly upregulated in ATC, and we wondered whether it might represent a therapeutic target in ATC patients. To investigate this hypothesis, the effects of harmine, a β-carboline alkaloid shown to induce degradation of the Twist1 protein and to possess antitumoral activity in different cancer types, were evaluated on two ATC-derived cell lines, BHT-101 and CAL-62. The results obtained demonstrated that, in both cell lines, harmine reduced the level of Twist1 protein and reverted the EMT, as suggested by the augmentation of E-cadherin and decrease in fibronectin expression. The drug also inhibited cell proliferation and migration in a dose-dependent manner and significantly reduced the anchorage-independent growth of both ATC cell lines. Harmine was also capable of inducing apoptosis in BHT-101 cells, but not in CAL-62 ones. Finally, the activation of PI3K/Akt signaling, but not that of the MAPK, was drastically reduced in treated cells. Overall, these in vitro data suggest that harmine could represent a new therapeutic option for ATC treatment.

In vitro and in vivo Efficacies of Novel Harmine Derivatives in the Treatment of Cystic Echinococcosis

Introduction

Cystic echinococcosis (CE) is a chronic zoonotic parasitic disease caused by the larvae of the Echinococcus granulosus sensu lato (s.l.) cluster. The current existing drugs have limited therapeutic efficacy against cystic echinococcosis, and thus, there is an urgent need to develop new drugs.

Methods

In this study, 7 harmine (HM) derivatives were screened and the effects of HM derivatives on E. granulosus sensu stricto (s.s.) were evaluated by in vitro and mouse experiments. The safety of the HM derivatives was assessed by cytotoxicity assays, acute toxicity study in animals and subacute toxicity study.

Results

These results show that the HM derivatives H-2-168 and DH-004 exhibited more significant antiparasitic effects at an initial concentration of 40 μM. The results of further studies showed that H-2-168 and DH-004 had dose-dependent effects against protoscoleces and had satisfactory therapeutic outcomes in vivo. Electron microscopy observations demonstrated that H-2-168 and DH-004 caused severe disruption of the parasite ultrastructure. Notably, the results of the acute toxicity and subchronic toxicity studies showed that H-2-168 and DH-004 had significantly improved safety. In addition, we found that H-2-168 and DH-004 induced DNA damage in E. granulosus s.s., which may be the mechanism by which these drugs produce their therapeutic effects.

Discussion

Overall, the data from this work demonstrate that H-2-168 and DH-004 are highly effective candidate compounds with low toxicity for the treatment of CE and will provide a new therapeutic strategy for CE pharmacological treatment.

Synthesis, and biological evaluation of pyrazole matrine derivatives as an insecticide against Spodoptera frugiperda

As one of the major threats to global food security, Spodoptera frugiperda (S. frugiperda) is highly gaining consideration due to its severe damage. Matrine is a widely and effectively used botanical insecticide in controlling S.frugiperda but lacks a rapidly available effect. To further improved the insecticidal activity of matrine based on combination principles, this work synthesized five new pyrazole matrine derivatives (PMDs) using Michael addition and investigated insecticidal activity against 2nd instar larvae of S. frugiperda(in vivo) and its isolated cell(in vitro). Our result demonstrated that PMDs show higher pesticidal activity than that matrine in both in vitro and in vivo assays. The most toxic derivatives in vitro and in vivo are PMD-3 and PMD-1, with IC50 of 2.49 mM and LC50 of 22.76 mg/L respectively. This research also investigates the anti-proliferation mechanism of PMDs based on isolated cells. PMDs decrease mitochondria membrane potential, arrested cell cycle at the G2/M phase, and upregulated Caspase 3, Caspase 9, and Apaf-1 to induce Caspase-dependent apoptosis. For Caspase-independent apoptosis, AIF and Endo G were found to be upregulated. Besides, pro-apoptotic factors like p53, IBM-1, and anti-apoptotic factors like IAP were upregulated. Moreover, we supposed that there was a linkage between lysosomes and PMD-induced apoptosis according to increased apoptosis rate, activated lysosomes, and upregulated Cathepsin B. This research provides new ideas for the synthesis of matrine derivatives and further demonstrated the anti-proliferation mechanism of PMDs.

Contribution of κ-/ι-carrageenan on the gelling properties of shrimp myofibrillar protein and their interaction mechanism exploration

BACKGROUND

The contribution and mechanism of κ-/ι-carrageenan (CG) with different hydration characteristics on the gelling properties of shrimp myofibrillar protein (MP) gelation was studied.

RESULTS

The gel strength, water-holding capacity and viscoelastic properties of MP gels were significantly enhanced by 1.0% κ-/ι-CG (P < 0.05), but the microstructure showed that excessive carrageenan caused fragmentation of the gel network and a corresponding decrease in gel properties. Compared to MP-ιCG, MP-κCG showed larger breaking force and shorter breaking distance, thus enhancing the hardness and brittleness of the gel, which might be ascribed to a reinforced network skeleton and a tighter binding of κCG-myosin. However, MP-ιCG stabilized more moisture in the gel network, thereby improving the tenderness of the gel, which might be related to the electrostatic repulsion observed between the sulfate groups of ιCG and the myosin observed by molecular docking. In addition, the β-sheet content and intermolecular interactions might be positively correlated with gel properties.

CONCLUSION

In this study, a composite gel system was constructed based on the interaction of MP and CG. The quality differences of two kinds of CG-MP gels were clarified, which will provide guidance for the application of different kinds of carrageenan and the development of recombinant meat products with specific quality. © 2022 Society of Chemical Industry.

Insect Cell-Based Models: Cell Line Establishment and Application in Insecticide Screening and Toxicology Research

During the past decades, research on insect cell culture has grown tremendously. Thousands of lines have been established from different species of insect orders, originating from several tissue sources. These cell lines have often been employed in insect science research. In particular, they have played important roles in pest management, where they have been used as tools to evaluate the activity and explore the toxic mechanisms of insecticide candidate compounds. This review intends to first briefly summarize the progression of insect cell line establishment. Then, several recent studies based on insect cell lines coupled with advanced technologies are introduced. These investigations revealed that insect cell lines can be exploited as novel models with unique advantages such as increased efficiency and reduced cost compared with traditional insecticide research. Most notably, the insect cell line-based models provide a global and in-depth perspective to study the toxicology mechanisms of insecticides. However, challenges and limitations still exist, especially in the connection between in vitro activity and in vivo effectiveness. Despite all this, recent advances have suggested that insect cell line-based models promote the progress and sensible application of insecticides, which benefits pest management.

Harmine and 7,8-dihydroxyflavone synergistically suitable for amyotrophic lateral sclerosis management: An in silico study

Introduction: Amyotrophic lateral sclerosis (ALS) is a fatal neurological disease characterized by progressive degeneration of both upper and lower motor neurons, resulting in paralysis and eventually leads to death from respiratory failure typically within 3 to 5 years of symptom onset. The aim of this work was to predict the pharmacokinetics and identify unique protein targets that are associated with potential anti-ALS phytochemicals and FDA-approved drugs, by in silico approaches.

Materials and methods: Standard computational tools (webserver and software) were used, and the methods used are clustering analysis, pharmacokinetics and molecular target predictions, and molecular docking simulation.

Results and discussion: The results show that riluzole, β-asarone, cryptotanshinone, harmine and 7,8-dihydroxyflavone have similar pharmacokinetics properties. Riluzole and harmine show 95% probability of target on norepinephrine transporter. Huperzine-A and cryptotanshinone show 100% probability of target on acetylcholinesterase. 7,8-dihydroxyflavone shows 35% probability of target on several carbonic anhydrases, 40% probability of target on CYP19A1, and 100% probability of target on inhibitor of nuclear factor kappa B kinase beta subunit and neurotrophic tyrosine kinase receptor type 2, respectively. Harmine also shows 95% probability of target on dual specificity tyrosine-phosphorylation-regulated kinases, threonine-protein kinases (haspin and PIM3), adrenergic receptors, cyclin-dependent kinases (CDK5 and CDK9), monoamine oxidase A, casein kinase I delta, serotonin receptors, dual specificity protein kinases (CLK1, CLK2, and CLK4), and nischarin, respectively. Also, the results of gene expression network show possible involvement of CDK1, CDK2, CDK4, ERK1, ERK2 and MAPK14 signaling pathways. This study shows that riluzole and harmine have closely similar physicochemical and pharmacokinetics properties as well as molecular targets, such as norepinephrine transporter (SLC6A2). Harmine, huperzine-A and cryptotanshinone could modulate acetylcholinesterase (AChE), which is involved in ALS-pathogenesis. The impact of 7,8-dihydroxyflavone on several carbonic anhydrases (CA) I, II, VII, IX, XII, and XIV, as well as CYP19A1, could help in remediating the respiratory failure associated with ALS.

Conclusion: Overall, harmine is found to be superior to riluzole, and the combination of harmine with 7,8-dihydroxyflavone can provide more effective treatment for ALS than the current regime. Further work is needed to validate the predicted therapeutic targets of harmine identified in this study on ALS model or clinical trials, using in silico, in vitro and in vivo techniques.

Graphical abstract:

Octanoic Acid-An Insecticidal Metabolite of Conidiobolus coronatus (Entomopthorales) That Affects Two Majors Antifungal Protection Systems in Galleria mellonella (Lepidoptera): Cuticular Lipids and Hemocytes

The food flavour additive octanoic acid (C8:0) is also a metabolite of the entomopathogenic fungus Conidiobolus coronatus, which efficiently infects and rapidly kills Galleria mellonella. GC-MS analysis confirmed the presence of C8:0 in insecticidal fraction FR3 extracted from C. coronatus filtrate. Topical administration of C8:0 had a dose-dependent effect on survival rates of larvae but not on pupation or adult eclosion times of the survivors. Topically applied C8:0 was more toxic to adults than larvae (LD100 for adults 18.33 ± 2.49 vs. 33.56 ± 2.57 µg/mg of body mass for larvae). The administration of C8:0 on the cuticle of larvae and adults, in amounts corresponding to their LD50 and LD100 doses, had a considerable impact on the two main defense systems engaged in protecting against pathogens, causing serious changes in the developmental-stage-specific profiles of free fatty acids (FFAs) covering the cuticle of larvae and adults and damaging larval hemocytes. In vitro cultures of G. mellonella hemocytes, either directly treated with C8:0 or taken from C8:0 treated larvae, revealed deformation of hemocytes, disordered networking, late apoptosis, and necrosis, as well as caspase 1-9 activation and elevation of 8-OHdG level. C8:0 was also confirmed to have a cytotoxic effect on the SF-9 insect cell line, as determined by WST-1 and LDH tests.

Effects of camptothecin on histological structures and gene expression profiles of fat bodies in Spodoptera frugiperda

Spodoptera frugiperda is a serious threat to global food production. Our previous study demonstrated that Camptothecin (CPT), a bioactive secondary metabolite from Camptotheca acuminata (Decne: Nyssaceae), exhibits adverse impact on the larval midgut of S. frugiperda and inhibits insect growth. However, effects of CPT on fat bodies of S. frugiperda larvae have not been examined yet. In the present study, we found that histological structures of fat bodies of S. frugiperda larvae were damaged in insects treated with CPT. Comparative transcriptomic analyses among different fat body samples from controls and insects treated with 1.0 and 5.0 μg/g CPT were performed. A total of 4212 and 5044 differentially expressed genes (DEGs) were identified in the samples treated with 1.0 and 5.0 μg/g CPT, respectively. Our data indicated that the pathways of detoxification, immune response, fatty acids, chitin, and hormone biosynthesis in fat bodies were affected by CPT treatments based on DEGs. These results provided a comprehensive view of the damage and gene expression changes in fat bodies of S. frugiperda after CPT exposure, which shall be useful to reveal the mechanism of CPT toxicity against S. frugiperda in future.

Acetylcholinesterase promotes apoptosis in insect neurons

Apoptosis plays a major role in development, tissue renewal and the progression of degenerative diseases. Studies on various types of mammalian cells reported a pro-apoptotic function of acetylcholinesterase (AChE), particularly in the formation of the apoptosome and the degradation of nuclear DNA. While three AChE splice variants are present in mammals, invertebrates typically express two ache genes that code for a synaptically located protein and a protein with non-synaptic functions respectively. In order to investigate a potential contribution of AChE to apoptosis in insects, we selected the migratory locust Locusta migratoria. We established primary neuronal cultures of locust brains and characterized apoptosis progression in vitro. Dying neurons displayed typical characteristics of apoptosis, including caspase-activation, nuclear condensation and DNA fragmentation visualized by TUNEL staining. Addition of the AChE inhibitors neostigmine and territrem B reduced apoptotic cell death under normal culture conditions. Moreover, both inhibitors completely suppressed hypoxia-induced neuronal cell death. Exposure of live animals to severe hypoxia moderately increased the expression of ace-1 in locust brains in vivo. Our results indicate a previously unreported role of AChE in insect apoptosis that parallels the pro-apoptotic role in mammalian cells. This similarity adds to the list of apoptotic mechanisms shared by mammals and insects, supporting the hypothesized existence of an ancient, complex apoptosis regulatory network present in common ancestors of vertebrates and insects.

A review on β-carboline alkaloids and their distribution in foodstuffs: A class of potential functional components or not?

Pharmacologically active β-carboline alkaloids (βCs) such as harman, norharman and some others are naturally present in plants and occur in many foodstuffs. They have a lot of pharmacological properties, including antitumor, antioxidant, anti-inflammatory and antimicrobial effects, and possess the potential for treating Alzheimer's disease, Parkinson's disease, depression and other central nervous system diseases. Dietary intake is proven to be an important source of βCs. Therefore, it is important to know the amounts of βCs that can be gotten from daily diets. This review summarizes the pharmacological activities, toxicology and formation of βCs, and gives collective information on contents of βCs in different foodstuffs.

Pharmacological effects of harmine and its derivatives: a review

Harmine is isolated from the seeds of the medicinal plant, Peganum harmala L., and has been used for thousands of years in the Middle East and China. Harmine has many pharmacological activities including anti-inflammatory, neuroprotective, antidiabetic, and antitumor activities. Moreover, harmine exhibits insecticidal, antiviral, and antibacterial effects. Harmine derivatives exhibit pharmacological effects similar to those of harmine, but with better antitumor activity and low neurotoxicity. Many studies have been conducted on the pharmacological activities of harmine and harmine derivatives. This article reviews the pharmacological effects and associated mechanisms of harmine. In addition, the structure-activity relationship of harmine derivatives has been summarized.

A Novel Insecticidal Molecule Extracted from Alpinia galanga with Potential to Control the Pest Insect Spodoptera frugiperda

Simple Summary

The fall armyworm is an insect pest that feeds on many plants, including plants of agronomic importance, such as corn and rice. In addition, it has developed resistance to the main families of synthetic insecticides. There is, therefore, a need to find new, more environmentally friendly molecules to control this pest. We have extracted a molecule from greater galangal and tested its activity as an insecticide on the fall armyworm. This natural molecule causes larval growth inhibition and larval developmental abnormalities. To understand its action, a cell model with Sf9 cells was used. The molecule is much more toxic to insect cells than to human cells. It affects cell proliferation and induces cell death. This study demonstrates that a molecule extracted from an edible plant may have potential in the future development of botanical insecticides for the control of insect pests.

Abstract

Spodoptera frugiperda, a highly polyphagous insect pest from America, has recently invaded and widely spread throughout Africa and Asia. Effective and environmentally safe tools are needed for successful pest management of this invasive species. Natural molecules extracted from plants offer this possibility. Our study aimed to determine the insecticidal efficacy of a new molecule extracted from Alpinia galanga rhizome, the 1′S-1′-acetoxychavicol acetate (ACA). The toxicity of ACA was assessed by topical application on early third-instar larvae of S. frugiperda. Results showed that ACA caused significant larval growth inhibition and larval developmental abnormalities. In order to further explore the effects of this molecule, experiments have been performed at the cellular level using Sf9 model cells. ACA exhibited higher toxicity on Sf9 cells as compared to azadirachtin and was 38-fold less toxic on HepG2 cells. Inhibition of cell proliferation was observed at sublethal concentrations of ACA and was associated with cellular morphological changes and nuclear condensation. In addition, ACA induced caspase-3 activity. RT-qPCR experiments reveal that ACA induces the expression of several caspase genes. This first study on the effects of ACA on S. frugiperda larvae and cells provides evidence that ACA may have potential as a botanical insecticide for the control of S. frugiperda.

Analysis of inhibitory interaction between epigallocatechin gallate and alpha-glucosidase: A spectroscopy and molecular simulation study

Alpha-glucosidase is one of the main enzymes responsible for digesting starch. Inhibiting its activity is therefore being targeted as a strategy for tackling diabetes. Certain food components have the potential to act as natural α-glucosidase (SCG) inhibitors, such as the polyphenols found in tea. In this study, epigallocatechin gallate (EGCG) was shown to strongly inhibit SCG activity (IC₅₀ value = 3.7 × 10^-5 M). Multi-spectroscopic binding molecular simulations indicated that EGCG spontaneously bound to SCG through a combination of hydrogen bonding and hydrophobic interactions. The hypothesis was supported by the results from intrinsic fluorescence quenching, conformational change, surface hydrophobicity decrease, and molecular docking analysis of the SCG after binding. Molecular docking provided powerful visual insights into the nature of the molecular interactions involved. This research provides important new information about the interaction mechanism of EGCG and SCG, which may be beneficial to the development of functional foods to prevent diabetes.

Natural harmine negatively regulates the developmental signaling network of Drosophila melanogaster (Drosophilidae: Diptera) in vivo

The widely distributed β-carboline alkaloids exhibit promising psychopharmacological and biochemical effects. Harmine, a natural β-carboline, can inhibit insect growth and development with unclear mechanisms. In this study, harmine (at 0-200 mg/L) showed a dose-dependent inhibitory effect on the pupal weight, length, height, pupation rate and eclosion rate of fruit flies Drosophila melanogaster, which was similar to the inhibition induced by the well-known botanical insect growth regulator azadirachtin. Moreover, the expression levels of major regulators from the developmental signaling network were down-regulated during the pupal stage except Numb, Fringe, Yorkie and Pten. The Notch, Wnt, Hedgehog and TGF-β pathways mainly played vital roles in coping with harmine exposure in pupae stage, while the Hippo, Hedgehog and TGF-β elements were involved in the sex differences. Notch, Hippo, Hedgehog, Dpp and Armadillo were proved to be suppressed in the developmental inhibition with fly mutants, while Numb and Punt were increased by harmine. In conclusion, harmine significantly inhibited the development of Drosophila by negatively affecting their developmental signaling network during different stages. Our results establish a preliminary understanding of the developmental signaling network subjected to botanical component-induced growth inhibition and lay the groundwork for further application.

Induction of Chemerin on Autophagy and Apoptosis in Dairy Cow Mammary Epithelial Cells

Involution of the mammary gland is a complex process controlled by various endocrine hormones and cytokine. As a novel adipocytokine, Chemerin not only plays a pivotal role in physiological and pathological processes such as immune response and lipid metabolism, but is also involved in the regulation of programmed cell death, including autophagy and apoptosis. The purpose of the present study was to elucidate whether autophagy and apoptosis of bovine mammary epithelial cells (BMECs) was triggered by Chemerin. BMECs were cultured and treated with Chemerin in vitro. The expression of autophagosome-forming marker, microtubule-associated protein 1 light chain 3 II (LC3-II) and sequestosome-1 (SQSTM 1, best known as p62), a substrate of autophagosome degradation were detected. The result showed that Chemerin significantly decreased the expression of p62 and markedly induced the conversion of LC3-I to LC3-II. The ratio of Bcl2-associated X and B-cell lymphoma-2 (Bax/Bcl-2) and the activity of caspase-3 were up-regulated after being treated by Chemerin, and the apoptotic rate was also significantly increased. These results suggested that Chemerin promoted the occurrence of autophagy and apoptosis in BMECs. Chloroquine (CQ), which is an inhibitor of autophagy. To explore effects of Chemerin on apoptosis, we prevented Chemerin-induced autophagy by pre-adding CQ in BMECs. Interestingly, this part of the experiment helped us find that all effects of Chemerin on apoptosis of BMECs could be enhanced with the inhibition of autophagy. Our study demonstrates that Chemerin-induced autophagy and apoptosis are mutually regulated in BMECs, but the specific mechanism remains to be further researched.

Harmine suppresses the proliferation of pancreatic cancer cells and sensitizes pancreatic cancer to gemcitabine treatment

Purpose

Pancreatic carcinoma is one of the most deadliest types of cancer, and relatively insensitive to the currently available chemotherapy. Thus, the discovery of novel therapeutic agents to prolong the survival times of patients with pancreatic cancer is urgently required.

Methods

Cell proliferation was assessed using the sulforhodamine B and cell clone formation assay, apoptosis was analyzed through Annexin V/PI staining, analysis of cell cycle distribution was determined by PI staining, and the expression of proteins was detected via Western blotting.

Results

Our data showed that harmine exerted an anti-proliferative effect and cell cycle arrest at G2/M in pancreatic cancer cells. Meanwhile, harmine plus gemcitabine showed strong synergy in inhibiting the proliferation of pancreatic cancer cells. Furthermore, harmine induced apoptosis and enhanced the gemcitabine-induced apoptosis in pancreatic cancer cells. The AKT/mTOR pathway is involved in mechanisms of gemcitabine resistance in pancreatic cancer cells, our data demonstrated that harmine plus gemcitabine significantly suppressed the AKT/mTOR signaling pathway.

Conclusion

Harmine may be a potential candidate for the treatment of pancreatic cancer. Morever, the combination of harmine with gemcitabine appears to be an attractive option for the treatment of patients with pancreatic cancer.

A novel polysaccharide from Lentinus edodes mycelia protects MIN6 cells against high glucose-induced damage via the MAPKs and Nrf2 pathways

Background

Diabetes mellitus is one of the most widespread diseases in the world, high glucose can damage islet cells, it is important to discover new natural products to inhibit high glucose damage. The protective effects and mechanisms of a novel Lentinus edodes mycelia polysaccharide (LMP) against damage induced by high glucose in MIN6 cells were explored.

Methods

Cell viability, malondialdehyde (MDA) inhibition, lactate dehydrogenase (LDH) release and the activity of superoxide dismutase (SOD) were evaluated under 40 mM glucose with or without LMP for 48 h. Cell signaling pathway analysis was performed to investigate the possible mechanisms of the protective effects of LMP in MIN6 cells.

Results

The results showed that LMP could increase cell viability and the activity of SOD, decrease the reactive oxygen species ( ROS) production, and reduce the MDA content and LDH release in high glucose-induced MIN6 cells. Moreover, LMP prevented high glucose-induced apoptosis by decreasing the expression of Bax and the activation of caspase-1 and caspase-3. Cell signaling pathway analysis showed that p38 mitogen-activated protein kinase (MAPK) and JNK pathways were inhibited and the Nrf2 pathway was activated after treated with LMP.

Conclusion

The protective effects of LMP against MIN6 cells damage induced by high glucose might rely on the regulation of the MAPK and Nrf2 pathways. These results indicated that LMP had great potential as a therapeutic agent for the treatment of diabetes mellitus.

Herbal medicine as an auspicious therapeutic approach for the eradication of Helicobacter pylori infection: A concise review

Helicobacter pylori (H. pylori) causes gastric mucosa inflammation and gastric cancer mostly via several virulence factors. Induction of proinflammatory pathways plays a crucial role in chronic inflammation, gastric carcinoma, and H. pylori pathogenesis. Herbal medicines (HMs) are nontoxic, inexpensive, and mostly anti-inflammatory reminding meticulous emphasis on the elimination of H. pylori and gastric cancer. Several HM has exerted paramount anti-H. pylori traits. In addition, they exert anti-inflammatory effects through several cellular circuits such as inhibition of 5'-adenosine monophosphate-activated protein kinase, nuclear factor-κB, and activator protein-1 pathway activation leading to the inhibition of proinflammatory cytokines (interleukin 1α [IL-1α], IL-1β, IL-6, IL-8, IL-12, interferon γ, and tumor necrosis factor-α) expression. Furthermore, they inhibit nitrous oxide release and COX-2 and iNOS activity. The apoptosis induction in Th1 and Th17-polarized lymphocytes and M2-macrophagic polarization and STAT6 activation has also been exhibited. Thus, their exact consumable amount has not been revealed, and clinical trials are needed to achieve optimal concentration and their pharmacokinetics. In the aspect of bioavailability, solubility, absorption, and metabolism of herbal compounds, nanocarriers such as poly lactideco-glycolide-based loading and related formulations are helpful. Noticeably, combined therapies accompanied by probiotics can also be examined for better clearance of gastric mucosa. In addition, downregulation of inflammatory microRNAs (miRNAs) by HMs and upregulation of those anti-inflammatory miRNAs is proposed to protect the gastric mucosa. Thus there is anticipation that in near future HM-based formulations and proper delivery systems are possibly applicable against gastric cancer or other ailments because of H. pylori.