Lipid Modulating Anti-oxidant Stress Activity of Gastrodin on Nonalcoholic Fatty Liver Disease Larval Zebrafish Model

Gastrodin exerts perioperative myocardial protection by improving mitophagy through the PINK1/Parkin pathway to reduce myocardial ischemia-reperfusion injury

BACKGROUND

Although blood flow is restored after treatment of myocardial infarction (MI), myocardial ischemia and reperfusion (I/R) can cause cardiac injury, which is a leading cause of heart failure. Gastrodin (GAS) exerts protective effects against brain, heart, and kidney I/R. However, its pharmacological mechanism in myocardial I/R injury (MIRI) remains unclear.

PURPOSE

GAS regulates autophagy in various diseases, such as acute hepatitis, vascular dementia, and stroke. We hypothesized that GAS could repair mitochondrial damage and regulate autophagy to protect against MIRI.

STUDY DESIGN

Male C57BL/6 mice and H9C2 cells were subjected to I/R and hypoxia-reoxygenation (H/R) injury after GAS administration, respectively, to assess the impact of GAS on cardiomyocyte phenotypes, heart, and mitochondrial structure and function. The effect of GAS on cardiac function and mitochondrial structure in patients undergoing cardiac surgery has been observed in clinical practice.

METHODS

The effects of GAS on cardiac structure and function, mitochondrial structure, and expression of related molecules in an animal model of MIRI were evaluated using immunohistochemical staining, enzyme-linked immunosorbent assay (ELISA), transmission electron microscopy, western blotting, and gene sequencing. Its effects on the morphological, molecular, and functional phenotypes of cardiomyocytes undergoing H/R were observed using immunohistochemical staining, real-time quantitative PCR, and western blotting.

RESULTS

GAS significantly reduces myocardial infarct size and improves cardiac function in MIRI mice in animal models and increases cardiomyocyte viability and reduces cardiomyocyte damage in cellular models. In clinical practice, myocardial injury was alleviated with better cardiac function in patients undergoing cardiac surgery after the application of GAS; improvements in mitochondria and autophagy activation were also observed. GAS primarily exerts cardioprotective effects through activation of the PINK1/Parkin pathway, which promotes mitochondrial autophagy to clear damaged mitochondria.

CONCLUSION

GAS can promote mitophagy and preserve mitochondria through PINK1/Parkin, thus indicating its tremendous potential as an effective perioperative myocardial protective agent.

Evaluation of the citalopram toxicity on early development of zebrafish: Morphological, physiological and biochemical responses

Citalopram, an antidepressant drug have been detected in different environmental matrices due to its high consumption. Previous study has proved that citalopram may alter the behaviour of aquatic organisms at environmentally relevant concentrations. However, scientific knowledge is still lacking on the ecotoxicological effects of citalopram on aquatic organisms. For this reason, the present study is aimed to investigate the potential toxicity of citalopram in terms of development, antioxidant, neurotoxicity, apoptosis, lipogenesis, and bone mineralization in embryonic and larval zebrafish (Danio rerio) at environmentally relevant concentrations. We noticed that citalopram exposure at 1 and 10 μg/L concentration delays hatching and heartbeat at 24, 48, 72 and 96 hpf. Exposure to citalopram also significantly increased mortality at 10 μg/L. Abnormal development with yolk sac edema, pericardial edema and scoliosis were also observed after citalopram treatment. In addition, citalopram significantly (P < 0.001) induced superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST) and lipid peroxidation (LPO) levels. A significant decrease in acetylcholine esterase (AChE) activity was also observed in citalopram exposed groups. We found significant dose-and time-dependent increases in apoptosis, lipogenesis, and bone mineralization. In conclusion, the findings of the present study can provide new insights on the ecotoxicity of citalopram in the aquatic environment.

Combined effects of vitamin D3 and dioxopiperidinamide derivative on lipid homeostasis, inflammatory pathways, and redox imbalance in non-alcoholic fatty liver disease in vivo zebrafish model

Liver damage and metabolic dysfunctions, the defining features of non-alcoholic fatty liver disease (NAFLD), are marked by inflammation, oxidative stress, and excessive hepatic fat accumulation. The current therapeutic approaches for NAFLD are limited, necessitating exploring novel treatment strategies. Dioxopiperidinamide derivatives, particularly DOPA-33, have shown effective anti-inflammatory and antioxidant properties, potentially offering therapeutic benefits against NAFLD. This study investigated the combined potential of vitamin D3 (Vit D3) and DOPA-33 in treating NAFLD. The network pharmacology analysis identified key NAFLD targets modulated by Vit D3 and DOPA-33, emphasizing their potential mechanisms of action. In NAFLD-induced zebrafish models, Vit D3 and DOPA-33 significantly reduced hepatic lipid accumulation, oxidative stress, and apoptosis, demonstrating superior efficacy over individual treatments. The treatment also lowered reactive oxygen species (ROS) levels, decreased liver damage, and enhanced antioxidant defense mechanisms. Moreover, behavioral analyses showed improved locomotion and reduced weight gain in treated zebrafish. Biochemical analyses revealed lower triglycerides (TG) and glucose levels with improved oxidative markers. Furthermore, histological analyses indicated reduced hepatic steatosis and inflammation, with decreased expression of lipogenesis-related genes and inflammatory mediators. Finally, high-performance liquid chromatography (HPLC) confirmed a significant reduction in hepatic cholesterol levels, indicating the effectiveness of the combination therapy in addressing key NAFLD-related dyslipidemias. These findings suggest that Vit D3 + DOPA-33 targets pathways involved in lipid metabolism, inflammation, and oxidative stress by offering a promising therapeutic approach for NAFLD.

Textile azo dye, Sudan Black B, inducing hepatotoxicity demonstrated in in vivo zebrafish larval model

Environmental pollution, particularly from textile industry effluents, raises concerns globally. The aim of this study is to investigate the hepatotoxicity of Sudan Black B (SBB), a commonly used textile azo dye, on embryonic zebrafish. SBB exposure led to concentration-dependent mortality, reaching 100% at 0.8 mM, accompanied by growth retardation and diverse malformations in zebrafish. Biochemical marker analysis indicated adaptive responses to SBB, including increased SOD, CAT, NO, and LDH, alongside decreased GSH levels. Liver morphology analysis unveiled significant alterations, impacting metabolism and detoxification. Also, glucose level was declined and lipid level elevated in SBB-exposed in vivo zebrafish. Inflammatory gene expressions (TNF-α, IL-10, and INOS) showcased a complex regulatory interplay, suggesting an organismal attempt to counteract pro-inflammatory states during SBB exposure. The increased apoptosis revealed a robust hepatic cellular response due to SBB, aligning with observed liver tissue damage and inflammatory events. This multidimensional study highlights the intricate web of responses due to SBB exposure, which is emphasizing the need for comprehensive understanding and targeted mitigation strategies. The findings bear the implications for both aquatic ecosystems and potentially parallels to human health, underscoring the imperative for sustained research in this critical domain.

Gastrodin: a comprehensive pharmacological review

Tianma is the dried tuber of Gastrodia elata Blume (G. elata), which is frequently utilized in clinical practice as a traditional Chinese medicine. Gastrodin (GAS) is the main active ingredient of Tianma, which has good pharmacological activity. Therefore, for the first time, this review focused on the extraction, synthesis, pharmacological effects, and derivatives of GAS and to investigate additional development options for GAS. The use of microorganisms to create GAS is a promising method. GAS has good efficacy in the treatment of neurological diseases, cardiovascular diseases, endocrine diseases, and liver diseases. GAS has significant anti-inflammatory, antioxidant, neuroprotective, vascular protective, blood sugar lowering, lipid-regulating, analgesic, anticancer, and antiviral effects. The mechanism involves various signaling pathways such as Nrf2, NF-κB, PI3K/AKT, and AMPK. In addition, the derivatives of GAS and biomaterials synthesized by GAS and PU suggested a broader application of GAS. The research on GAS is thoroughly summarized in this paper, which has useful applications for tackling a variety of disorders and exhibits good development value.

Chinese herbal medicines: The modulator of nonalcoholic fatty liver disease targeting oxidative stress

ETHNOPHARMACOLOGICAL RELEVANCE

Plants are a natural treasure trove; their secondary metabolites participate in several pharmacological processes, making them a crucial component in the synthesis of novel pharmaceuticals and serving as a reserve resource foundation in this process. Nonalcoholic fatty liver disease (NAFLD) is associated with the risk of progression to hepatitis and liver cancer. The "Treatise on Febrile Diseases," "Compendium of Materia Medica," and "Thousand Golden Prescriptions" have listed herbal remedies to treat liver diseases.

AIM OF THE REVIEW

Chinese herbal medicines have been widely used for the prevention and treatment of NAFLD owing to their efficacy and low side effects. The production of reactive oxygen species (ROS) during NAFLD, and the impact and potential mechanism of ROS on the pathogenesis of NAFLD are discussed in this review. Furthermore, common foods and herbs that can be used to prevent NAFLD, as well as the structure-activity relationships and potential mechanisms, are discussed.

METHODS

Web of Science, PubMed, CNKI database, Google Scholar, and WanFang database were searched for natural products that have been used to treat or prevent NAFLD in the past five years. The primary search was performed using the following keywords in different combinations in full articles: NAFLD, herb, natural products, medicine, and ROS. More than 400 research papers and review articles were found and analyzed in this review.

RESULTS

By classifying and discussing the literature, we obtained 86 herbaceous plants, 28 of which were derived from food and 58 from Chinese herbal medicines. The mechanism of NAFLD was proposed through experimental studies on thirteen natural compounds (quercetin, hesperidin, rutin, curcumin, resveratrol, epigallocatechin-3-gallate, salvianolic acid B, paeoniflorin, ginsenoside Rg1, ursolic acid, berberine, honokiol, emodin). The occurrence and progression of NAFLD could be prevented by natural antioxidants through several pathways to prevent ROS accumulation and reduce hepatic cell injuries caused by excessive ROS.

CONCLUSION

This review summarizes the natural products and routinely used herbs (prescription) in the prevention and treatment of NAFLD. Firstly, the mechanisms by which natural products improve NAFLD through antioxidant pathways are elucidated. Secondly, the potential of traditional Chinese medicine theory in improving NAFLD is discussed, highlighting the safety of food-medicine homology and the broader clinical potential of multi-component formulations in improving NAFLD. Aiming to provide theoretical basis for the prevention and treatment of NAFLD.

Non-Genetic-Induced Zebrafish Model for Type 2 Diabetes with Emphasis on Tools in Model Validation

The unrelenting increase in the incidence of type 2 diabetes (T2D) necessitates the urgent need for effective animal models to mimic its pathophysiology. Zebrafish possess human-like metabolic traits and share significant genetic similarities, making them valuable candidates for studying metabolic disorders, including T2D. This review emphasizes the critical role of animal models in diabetes research, especially focusing on zebrafish as an alternative model organism. Different approaches to a non-genetic model of T2D in zebrafish, such as the glucose solution, diet-induced, chemical-induced, and combined diet-induced and glucose solution methods, with an emphasis on model validation using indicators of T2D, were highlighted. However, a significant drawback lies in the validation of these models. Some of these models have not extensively demonstrated persistent hyperglycemia or response to insulin resistance and glucose tolerance tests, depicted the morphology of the pancreatic β-cell, or showed their response to antidiabetic drugs. These tools are crucial in T2D pathology. Future research on non-genetic models of T2D in zebrafish must extensively focus on validating the metabolic deficits existing in the model with the same metabolic defects in humans and improve on the existing models for a better understanding of the molecular mechanisms underlying T2D and exploring potential therapeutic interventions.

Review on pharmacological effects of gastrodin

Gastrodia elata Blume is a well-known traditional Chinese medicine that is mainly used to treat diseases related to the nervous system, such as stroke, epilepsy, and headache. Gastrodin is the main bioactive component of Gastrodia elata Blume, and studies have shown that it has extensive pharmacological activity. This narrative review aims to systematically review relevant studies on the pharmacological effects of gastrodin to provide researchers with the latest and most useful information. Studies have shown that gastrodin has prominent neuroprotective effects and can treat or improve epilepsy, Tourette syndrome, Alzheimer's disease, Parkinson's disease, emotional disorders, cerebral ischemia-reperfusion injury, cognitive impairment, and neuropathic pain. Gastrodin can also improve myocardial hypertrophy, hypertension, and myocardial ischemia-reperfusion injury. In addition, gastrodin can mitigate liver, kidney, and bone tissue damage caused by oxidative stress and inflammation. In short, gastrodin is expected to treat many diseases, and it is worth investing more effort in research on this compound.

Preventive and therapeutic effects of natural products and herbal extracts on nonalcoholic fatty liver disease/nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is a common condition that is prevalent in patients who consume little or no alcohol, and is characterized by excessive fat accumulation in the liver. The disease is becoming increasingly common with the rapid economic development of countries. Long-term accumulation of excess fat can lead to NAFLD, which represents a global health problem with no effective therapeutic approach. NAFLD is a complex, multifaceted pathological process that has been the subject of extensive research over the past few decades. Herbal medicines have gained attention as potential therapeutic agents to prevent and treat NAFLD due to their high efficacy and low risk of side effects. Our overview is based on a PubMed and Web of Science database search as of Dec 22 with the keywords: NAFLD/NASH Natural products and NAFLD/NASH Herbal extract. In this review, we evaluate the use of herbal medicines in the treatment of NAFLD. These natural resources have the potential to inform innovative drug research and the development of treatments for NAFLD in the future.

Zebrafish facilitate non-alcoholic fatty liver disease research: Tools, models and applications

Non-alcoholic fatty liver disease (NAFLD) has become an increasingly epidemic metabolic disease worldwide. NAFLD can gradually deteriorate from simple liver steatosis, inflammation and fibrosis to liver cirrhosis and/or hepatocellular carcinoma. Zebrafish are vertebrate animal models that are genetically and metabolically conserved with mammals and have unique advantages such as high fecundity, rapid development ex utero and optical transparency. These features have rendered zebrafish an emerging model system for liver diseases and metabolic diseases favoured by many researchers in recent years. In the present review, we summarize a series of tools for zebrafish NAFLD research and the models established through different dietary feeding, hepatotoxic chemical treatments and genetic manipulations via transgenic or genome editing technologies. We also discuss how zebrafish models facilitate NAFLD studies by providing novel insights into NAFLD pathogenesis, toxicology research, and drug evaluation and discovery.

Gastrodia elata BI.:A Comprehensive Review of Its Traditional Use, Botany, Phytochemistry, Pharmacology, and Pharmacokinetics

Materials and Methods

This article collects information from relevant documents, including scientific papers, books, and dissertations concerning Gastrodia elata BI.

Results

To date, research on Gastrodia elata BI. has identified about 100 active compounds. Many compounds in Gastrodia elata BI. have biological activities, such as sedation and hypnosis, anticonvulsion, improvement of learning and memory, protection of neurons, antidepressive effects, lowering of blood pressure, promotion of angiogenesis, protection of cardiomyocytes, antiplatelet aggregation, anti-inflammatory activity, and amelioration of labor pains.

Conclusion

Although many traditional uses of this plant have been confirmed, it is necessary to continue to study the relationship between its structure and function, clarify the mechanisms of pharmacological effects, and explore new clinical applications so as to better delineate the quality control standards for Gastrodia elata BI.

Hepatoprotective effect of dihydroxy piperlongumine in high cholesterol-induced non-alcoholic fatty liver disease zebrafish via antioxidant activity

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are a growing epidemic and the most common liver diseases. Consumption of a western diet with high fats alters redox status, induces inflammation, and impairs the physiological function of hepatocytes. However, the pharmacological market lacks anti-NAFLD/NASH drugs. Long pepper (Piper longum L) is used in traditional Mongolian medicine for treating hyperlipidemia. Piperlongumine (PL) is a bioactive compound of Piper longum L, which usually possesses anticancer activities due to its ROS elevation property. However, when PL was demethylated they behave as an antioxidant. Previously, we found dihydroxy piperlongumine (DHPL) possesses high antioxidant activity among the hydroxy piperlongumines, which makes us curious to reveal the anti-NAFLD effect. A high-cholesterol diet (HCD) was chosen to induce NAFLD zebrafish model, and the antioxidant and lipid-lowering effects of DHPL were evaluated. Histological alterations of NAFLD were also scored along with gene expression to explore the molecular mechanism. DHPL reduced lipid accumulation in both short-term and long-term feeding trials. DHPL increases antioxidant activity and lipid-lowering gene expression and decreases hepatic triglyceride, oxidative stress, and lipogenic genes. In conclusion, DHPL halted the progression of HCD-induced NAFLD in the zebrafish model.

Therapeutic potential of bioactive phytoconstituents found in fruits in the treatment of non-alcoholic fatty liver disease: A comprehensive review

Nonalcoholic fatty liver disease (NAFLD), a chronic liver condition affects a large number of people around the world with a frequency of 25% of all the chronic liver disease worldwide. Several targets viz. anti-inflammatory, anti-apoptotic and, anti-fibrotic factors, anti-oxidant and insulin-sensitizing pathways, metabolic regulators as well as repurposing traditional medications have been studied for the pharmacologic therapy of NAFLD. Newer pharmacotherapies like caspases blockade, agonists of PPAR and farnesoid X receptor agonists are currently being investigated in treating human NAFLD. However, NAFLD has no FDA-approved pharmacological therapy, therefore there is a considerable unmet therapy need. Apart from the conventional treatment regime, the current approaches to treating NAFLD include lifestyle interventions including healthy diet with adequate nutrition and physical activity. Fruits are known to play a key role in the well-being of human health. Fruits are loaded with a repertoire of bioactive phytoconstituents like catechins, phytosterols, proanthocyanidin, genestin, daidzen, resveratrol, magiferin found in fruits like pear, apricot, strawberries, oranges, apples, bananas, grapes, kiwi, pineapple, watermelon, peach, grape seed and skin, mango, currants, raisins, dried dates, passion fruit and many more. These bioactive phytoconstituents are reported to demonstrate promising pharmacological efficacy like reduction in fatty acid deposition, increased lipid metabolism, modulation of insulin signaling pathway, gut microbiota and hepatic inflammation, inhibition of histone acetyltransferase enzymatic activity to name a few. Not only fruits, but their derivatives like oils, pulp, peel, or their preparations are also found to be equally beneficial in various liver diseases like NAFLD, NASH. Although most of the fruits contains potent bioactive phytoconstituents, however, the presence of sugar in fruits put a question mark on the ameliorative property of the fruits and there has been contrasting reports on the glycemic control post fruit consumption in type 2 diabetic patients. This review is an attempt to summarize the beneficial effects of fruit phytoconstituents on NAFLD based on epidemiological, clinical and experimental evidence, focusing especially on their mechanisms of action.

Antioxidant and anti-inflammatory agents in chronic liver diseases: Molecular mechanisms and therapy

Chronic liver disease (CLD) is a continuous process that causes a reduction of liver function lasting more than six months. CLD includes alcoholic liver disease (ALD), non-alcoholic fatty liver disease (NAFLD), chronic viral infection, and autoimmune hepatitis, which can lead to liver fibrosis, cirrhosis, and cancer. Liver inflammation and oxidative stress are commonly associated with the development and progression of CLD. Molecular signaling pathways such as AMP-activated protein kinase (AMPK), C-Jun N-terminal kinase, and peroxisome proliferator-activated receptors (PPARs) are implicated in the pathogenesis of CLD. Therefore, antioxidant and anti-inflammatory agents from natural products are new potent therapies for ALD, NAFLD, and hepatocellular carcinoma (HCC). In this review, we summarize some powerful products that can be potential applied in all the stages of CLD, from ALD/NAFLD to HCC. The selected agents such as β-sitosterol, curcumin, genistein, and silymarin can regulate the activation of several important molecules, including AMPK, Farnesoid X receptor, nuclear factor erythroid 2-related factor-2, PPARs, phosphatidylinositol-3-kinase, and lysyl oxidase-like proteins. In addition, clinical trials are undergoing to evaluate their efficacy and safety.

A New In Vivo Zebrafish Bioassay Evaluating Liver Steatosis Identifies DDE as a Steatogenic Endocrine Disruptor, Partly through SCD1 Regulation

Non-alcoholic fatty liver disease (NAFLD), which starts with liver steatosis, is a growing worldwide epidemic responsible for chronic liver diseases. Among its risk factors, exposure to environmental contaminants, such as endocrine disrupting compounds (EDC), has been recently emphasized. Given this important public health concern, regulation agencies need novel simple and fast biological tests to evaluate chemical risks. In this context, we developed a new in vivo bioassay called StAZ (Steatogenic Assay on Zebrafish) using an alternative model to animal experimentation, the zebrafish larva, to screen EDCs for their steatogenic properties. Taking advantage of the transparency of zebrafish larvae, we established a method based on fluorescent staining with Nile red to estimate liver lipid content. Following testing of known steatogenic molecules, 10 EDCs suspected to induce metabolic disorders were screened and DDE, the main metabolite of the insecticide DDT, was identified as a potent inducer of steatosis. To confirm this and optimize the assay, we used it in a transgenic zebrafish line expressing a blue fluorescent liver protein reporter. To obtain insight into DDE's effect, the expression of several genes related to steatosis was analyzed; an up-regulation of scd1 expression, probably relying on PXR activation, was found, partly responsible for both membrane remodeling and steatosis.

Plants-based medicine implication in the evolution of chronic liver diseases

Hepatic disorders are considered major health problems, due to their high incidence, increased risk of chronicling or death and the costs involved in therapies. A large number of patients with chronic liver diseases use herbal medicines and dietary supplements in parallel with allopathic treatment. The current review provides a thorough analysis of the studies conducted on the most important species of medicinal plants used in this disease, bioactive compounds and on the activity of herbal medicines in the evolution of chronic liver diseases. However, a negative aspect is that there is frequently a lack of comprehensive data on the progression of the illness and the living standards of patients who are affected when evaluating the effects of these phytocomponents on the evolution of chronic liver disease, the patients' health, and their quality of life. It is essential to take this impairment into account when evaluating the long-term effects of herbal treatments on the health of individuals who suffer from liver illness. Bioactive phytocomponents may be a suitable source for the development of novel medications due to the correlation between traditional uses and medical advances. Additional high-quality preclinical examinations utilizing cutting-edge approaches are needed to assess safety and effectiveness and to detect, categorize, and standardize the active substances and their formulations for the most suitable therapeutic management of liver illnesses.

Nimbin analogs N5 and N7 regulate the expression of lipid metabolic genes and inhibit lipid accumulation in high-fat diet-induced zebrafish larvae: An antihyperlipidemic study

BACKGROUND

Excess accumulation of lipids leads to obesity. Triterpenoids are a group of plant compounds which poses various biological activities. The biological activities of Nimbin analogs N5 and N7 were addressed in this study on inhibiting lipid aggregation and underlying the derivatives molecular mechanisms for a therapeutical approach.

AIM

This study aims to evaluate the anti-adipogenic activity of semi-natural Nimbin analogs, N5 and N7, on zebrafish larvae induced with oxidative stress due to a high-fat diet (HFD) and adipogenesis using specific fluorescent stains.

MATERIALS AND METHODS

Zebrafish at 4 days post fertilized (dpf) larvae were divided into groups for the HFD diet along with exposure to various concentrations of N5 and N7. HFD induced accumulation of neutral lipids and triglycerides (Oil Red O and Nile red staining, respectively) with weight gain, which generated intracellular ROS (DCFH-DA staining) and superoxide anion production (DHE staining) with depleted glutathione levels (NDA staining) were assayed. HFD exposure promoted the accumulation of inflammatory macrophages (Neutral red staining) and impaired glucose metabolism (2NBDG staining). The ability of N5 and N7 to reduce total regulating lipogenic specific genes C/EBP-α, SREBP-1 and FAS were evaluated using relative gene expression.

KEY FINDINGS

The Nimbin analogues N5 and N7 suppressed adipogenesis, forming intracellular ROS and superoxide anion while simultaneously restoring glutathione levels. The analogues significantly lowered total TC and TG levels, prevented inflammatory macrophage build-up and boosted glucose absorption. Also, N5 and N7 down-regulate the lipogenic-specific genes.

SIGNIFICANCE

Nimbin analogs N5 and N7 enhance lipolysis and inhibit adipogenesis in in-vivo zebrafish larvae model.

Recovery of a hypolipidemic polysaccharide from artificially cultivated Sanghuangporus vaninii with an effective method

In this study, an effective method was developed to extract the polysaccharide from Sanghuangporus vaninii (PFSV) by destroying the cell wall. Box-Behnken design was employed to determine the optimal processing conditions as follows: processing temperature (80°C), processing time (0.81 h) and amount of HCl (1.5 ml). Under these conditions, the yield of PFSV reached 5.94 ± 0.16%. The purified polysaccharide (PFSV-2) was found to be a hetero-polysaccharide with an average molecular weight of 20.377 kDa. The backbone of PFSV-2 was composed of an →6)-α-Galp-(1→ and →2,6)-β-Manp-(1→ and →2)-α-Fucp-(1→ and was branched of t-α-Manp-(1→ at position 2 of residue B. PFSV-2 showed hypolipidemic activity by decreasing lipid accumulation and the levels of total cholesterol and triglycerides in zebrafish larvae. Furthermore, PFSV-2 downregulated the pparg, fasn, and HMGCRb genes and upregulated the pparab and acaca genes. These findings suggested PFSV-2 may be a promising candidate in lipid regulation therapy.

6-Gingerdione Reduces Apoptotic Conditions in HepG2 Cells and Inhibits Inflammatory Cytokine Gene Expression in Alcoholic Liver Injured Zebrafish Larvae

Antioxidant natural products and their analogs especially phenolic compounds, exhibit diverse biological properties, including anti-inflammatory, antioxidant, and anticancer activities. Ginger which is widely used worldwide for various beneficial effects also contains several phenolic antioxidants, and 6-gingerol is one of the natural products studied extensively. However, the molecular mechanism of synthetically synthesized 6-gingerdione (compound 1) from 6-gingerol was not known. In this study, compound 1 and methylated 6-gingerdione (compound 2) were obtained semi synthetically from 6-gingerol. Compound 1 and 2 are subjected to SwissADME prediction. Then the protective effect of compound 1 was analyzed in 2 % EtOH induced HepG2 cells and zebrafish larvae. Hydroxyl and nitric oxide scavenging assays reveal that compound 1 showed more antioxidant activity than compound 2 at 50 μM. Moreover, compound 1 exhibited good anti-inflammatory activity via lipoxygenase inhibition and proteinase inhibition. Apoptosis and oxidative stress in HepG2 cells were induced by 2 % EtOH and treated with compound 1. Compound 1 significantly inhibited the EtOH induced nitric oxide production, apoptosis, and ROS generation in HepG2 cells. Encouraged by the in-vitro antioxidant and anti-inflammatory activities, compound 1 was then investigated for its protective effect in 2 % EtOH induced ALD zebrafish larva. Compound 1 protected the zebrafish larvae from liver injury by suppressing inflammatory (COX-2, TNF-α, and IL-1β) and lipogenic genes (C/EBP-α, SREBP1, and IL-1β) while upregulating the antioxidant gene. Our findings indicate that compound 1 synthesized from 6-gingerol ameliorated liver injury that likely, contributes to its potential antioxidant and anti-inflammatory properties.

Exposure to environmental pollutant bisphenol A causes oxidative damage and lipid accumulation in Zebrafish larvae: Protective role of WL15 peptide derived from cysteine and glycine-rich protein 2

Humans are exposed to obesity causing Bisphenol A in various ways, especially through diet and food containers. Bioactive peptides are already reported to have antioxidant, antidiabetic, and antiobesity properties, which can mimic the role of mediators involved in obesity prevention. The protective effect of a short molecule or peptide, WL15 from cysteine and glycine-rich protein 2 of a teleost of aquatic resource on Bisphenol A (BPA)-induced lipid accumulation in zebrafish larvae was investigated. BPA exposure disrupted the antioxidant enzymes, apoptosis, and nitric oxide and led to changes in biochemical markers including alkaline phosphatase, lactate dehydrogenase, lipid peroxidation, glutathione S-transferases, glutathione peroxidase, and reduced glutathione. However, WL15 inhibited the overproduction of oxidative stress, which correlates with its lipid-lowering potential. BPA-induced lipid accumulation in zebrafish showed an increase in triglyceride, cholesterol, and glucose level; simultaneously, WL15 treatment significantly reduced such accumulation in zebrafish. Evidenced by Oil red O staining and Nile red assay, WL15 inhibited lipid accumulation. At the same time, WL15 at 50 µM increases 2-(N-[7-nitrobenz-2-oxa-1,3-diazol-4-yl]amino)-2-deoxy-d-glucose (2NBDG) glucose uptake in zebrafish. In addition, gene expression studies in zebrafish larvae demonstrated that the WL15 peptide could play a crucial role in preventing lipid accumulation by downregulating the expression of lipogenesis-specific genes. These results revealed an interesting and novel property of WL15, suggesting its potential application in preventing lipid accumulation through the hypolipidemic and antioxidant properties.

Gastrodin promotes the regeneration of peripheral nerves by regulating miR-497/BDNF axis

Background

Gastrodin (GAS), is a kind of phenolic compound extracted from the traditional Chinese herbal medicine Gastrodia elata Blume (GEB). This study was aimed at probing into the protective effect of GAS on peripheral nerve injury (PNI) and the underlying mechanism.

Methods

A rat model with PNI was established, followed by intraperitoneal injection of GAS (20 mg/kg/day). Sciatic nerve function index (SFI) was used to analyze the function of sciatic nerve. The amplitude and latency of compound muscle action potential (CMAP) were examined by electrophysiology. Schwann cells (SCs) were isolated from fetal rats and treated with GAS 200 μg/mL, and H₂O₂-induced model of oxidative stress injury was established. EdU and Transwell assays were adopted to detect the viability and migration of SCs. Dual-luciferase reporter gene assays were applied to verify the binding site between miR-497 and brain-derived neurotrophic factor (BDNF) 3’UTR. MiR-497 expression was probed by quantitative real-time polymerase chain reaction (qRT-PCR). BDNF, neurofilament-200 (NF-200) and myelin basic protein (MBP) expression levels were detected by Western blotting. Malondialdehyde (MDA) content, superoxide dismutase (SOD) activity, glutathione content (GSH) and catalase (CAT) activity in SCs were also measured.

Results

GAS treatment could significantly increase the SFI and amplitude of CMAP, shorten the refractory period, and ameliorate muscle atrophy of the rats with PNI. GAS treatment could markedly restrain miR-497 expression and increase the expression levels of BDNF, NF-200 and MBP in SCs. BDNF was confirmed as the target of miR-497 and BDNF overexpression could reverse the impacts of miR-497 overexpression on the proliferation, migration, and oxidative stress response of SCs.

Conclusions

GAS promotes the recovery of PNI via modulating miR-497 / BDNF axis and inhibiting oxidative stress.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-021-03483-z.

Validation of a Quantification Method for Curcumin Derivatives and Their Hepatoprotective Effects on Nonalcoholic Fatty Liver Disease

Curcumin (CM), demethoxycurcumin (DMC), and bisdemethoxycurcumin (BDMC) are major curcumin derivatives found in the rhizome of turmeric (Curcuma longa L.), and have yielded impressive properties to halt various diseases. In the present study, we carried out a method validation for curcumin derivatives and analyzed the contents simultaneously using HPLC with UV detection. For validation, HPLC was used to estimate linearity, range, specificity, accuracy, precision, limit of detection (LOD), and limit of quantification (LOQ). Results showed a high linearity of the calibration curve, with a coefficient of correlation (R²) for CM, DMC, and BDMC of 0.9999, 0.9999, and 0.9997, respectively. The LOD values for CM, DMC, and BDMC were 1.16, 1.03, and 2.53 ng/μL and LOQ values were 3.50, 3.11, and 7.67 ng/μL, respectively. Moreover, to evaluate the ability of curcumin derivatives to reduce liver lipogenesis and compare curcumin derivatives’ therapeutic effects, a HepG2 cell model was established to analyze their hepatoprotective properties. Regarding the in vivo study, we investigated the effect of DMC, CM, and BDMC on nonalcoholic fatty liver disease (NAFLD) caused by a methionine choline deficient (MCD)-diet in the C57BL/6J mice model. From the in vitro and in vivo results, curcumin derivatives alleviated MCD-diet-induced lipid accumulation as well as high triglyceride (TG) and total cholesterol (TC) levels, and the protein and gene expression of the transcription factors related to liver adipogenesis were suppressed. Furthermore, in MCD-diet mice, curcumin derivatives suppressed the upregulation of toll-like receptors (TLRs) and the production of pro-inflammatory cytokines. In conclusion, our findings indicated that all of the three curcuminoids exerted a hepatoprotective effect in the HepG2 cell model and the MCD-diet-induced NAFLD model, suggesting a potential for curcuminoids derived from turmeric as novel therapeutic agents for NAFLD.

An Overview of Zebrafish Modeling Methods in Drug Discovery and Development

Animal studies are recognized as a significant step forward in the bridging between drug discovery and clinical applications. Animal models, due to their relative genetic, molecular, physiological, and even anatomical similarities to humans, can provide a suitable platform for unraveling the mechanisms underlying human diseases and discovering new therapeutic approaches as well. Recently, zebrafish has attracted attention as a valuable experimental and pharmacological model in drug discovery and development studies due to its prominent characteristics such as the high degree of genetic similarity with humans, genetic manipulability, and prominent clinical features. Since advancing a theory to a valid and reliable observation requires the manipulation of animals, it is, therefore, essential to use efficient modeling methods appropriate to the different aspects of experimental conditions. In this context, applying several various approaches such as using chemicals, pathogens, and genetic manipulation approaches allows zebrafish development into a preferable model that mimics some human disease pathophysiology. Thus, such modeling approaches not only can provide a framework for a comprehensive understanding of the human disease mechanisms that have a counterpart in zebrafish but also can pave the way for discovering new drugs that are accompanied by higher amelioration effects on different human diseases.

Potential Natural Compounds for the Prevention and Treatment of Nonalcoholic Fatty Liver Disease: A Review on Molecular Mechanisms

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a kind of metabolic stress-induced liver injury closely related to insulin resistance and genetic susceptibility, and there is no specific drug for its clinical treatment currently. In recent years, a large amount of literature has reported that many natural compounds extracted from traditional Chinese medicine (TCM) can improve NAFLD through various mechanisms. According to the latest reports, some emerging natural compounds have shown great potential to improve NAFLD but are seldom used clinically due to the lacking special research.

PURPOSE

This paper aims to summarize the molecular mechanisms of the potential natural compounds on improving NAFLD, thus providing a direction and basis for further research on the pathogenesis of NAFLD and the development of effective drugs for the prevention and treatment of NAFLD.

METHODS

By searching various online databases, such as Web of Science, SciFinder, PubMed, and CNKI, NAFLD and these natural compounds were used as the keywords for detailed literature retrieval.

RESULTS

The pathogenesis of NAFLD and the molecular mechanisms of the potential natural compounds on improving NAFLD have been reviewed.

CONCLUSION

Many natural compounds from traditional Chinese medicine have a good prospect in the treatment of NAFLD, which can serve as a direction for the development of anti-NAFLD drugs in the future.

Gastrodin Improves Nonalcoholic Fatty Liver Disease Through Activation of the Adenosine Monophosphate-Activated Protein Kinase Signaling Pathway

BACKGROUND AND AIMS

NASH is currently one of the most common causes of liver transplantation and hepatocellular carcinoma. Thus far, there is still no effective pharmacological therapy for this disease. Recently, Gastrodin has demonstrated hepatoprotective effects in a variety of liver diseases. The aim of this study is to investigate the function of Gastrodin in NASH.

APPROACH AND RESULTS

In our study, Gastrodin showed potent therapeutic effects on NASH both in vivo and in vitro. In high-fat diet or high-fat and high-cholesterol diet-fed mice, the liver weight, hepatic and serum triglyceride and cholesterol contents, and serum alanine aminotransferase and aspartate aminotransferase activity levels were markedly reduced by Gastrodin treatment as compared with the corresponding vehicle groups. Notably, Gastrodin showed minimal effects on the function and histological characteristics of other major organs in mice. We further examined the effects of Gastrodin on lipid accumulation in primary mouse hepatocytes and human hepatocyte cell line and observed that Gastrodin showed a significant decrease in lipid accumulation and inflammatory response in hepatocytes under metabolic stress. Furthermore, RNA-sequencing analysis systemically indicated that Gastrodin suppressed the pathway and key regulators related to lipid accumulation, inflammation, and fibrosis in the pathogenesis of NASH. Mechanistically, we found that Gastrodin protected against NASH by activating the adenosine monophosphate-activated protein kinase (AMPK) pathway, which was supported by the result that the AMPK inhibitor Compound C or AMPK knockdown blocked the Gastrodin-mediated hepatoprotective effect.

CONCLUSIONS

Gastrodin attenuates steatohepatitis by activating the AMPK pathway and represents a therapeutic for the treatment of NASH.

P- Hydroxybenzyl Alcohol Alleviates Oxidative Stress in a Nonalcoholic Fatty Liver Disease Larval Zebrafish Model and a BRL-3A Hepatocyte Via the Nrf2 Pathway

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, and it has gradually become the main disease burden in the world. However, the pathogenesis of NAFLD is complex, involving such things as dyslipidemia, oxidative stress, inflammation, etc. This brings to the table a significant challenge for drug development, and there is still no drug approved by the FDA on the market to treat the disease. GAS and HBA are active ingredients of the orchidaceae plant gastrodia elata and have exhibit effects in ameliorating nervous system diseases caused by oxidative stress. HBA is a metabolite of GAS that could perform lipid regulation and improve oxidative stress on HCD-induced NAFLD larval zebrafish, as reported by previous studies; we therefore explored the role of HBA in lipid regulation and oxidative stress on HCD-induced NAFLD larval zebrafish in vivo and FFA-induced BRL-3A hepatocyte in vitro. The gene expression of lipogenesis, inflammation, and oxidative stress were measured to investigate the underlying mechanism of HBA, and the potential protein target of HBA was explored by immunofluorescence. Altogether, our data highlight the role of HBA in improving NAFLD by use of its lipid-lowering and anti-oxidative properties via the Nrf2/HO-1 signaling pathway, providing a potential therapeutic compound for NAFLD treatment.

Wild-Type Zebrafish (Danio rerio) Larvae as a Vertebrate Model for Diabetes and Comorbidities: A Review

Zebrafish have become a popular alternative to higher animals in biomedical and pharmaceutical research. The development of stable mutant lines to model target specific aspects of many diseases, including diabetes, is well reported. However, these mutant lines are much more costly and challenging to maintain than wild-type zebrafish and are simply not an option for many research facilities. As an alternative to address the disadvantages of advanced mutant lines, wild-type larvae may represent a suitable option. In this review, we evaluate organ development in zebrafish larvae and discuss established methods that use wild-type zebrafish larvae up to seven days post fertilization to test for potential drug candidates for diabetes and its commonly associated conditions of oxidative stress and inflammation. This provides an up to date overview of the relevance of wild-type zebrafish larvae as a vertebrate antidiabetic model and confidence as an alternative tool for preclinical studies. We highlight the advantages and disadvantages of established methods and suggest recommendations for future developments to promote the use of zebrafish, specifically larvae, rather than higher animals in the early phase of antidiabetic drug discovery.

Puerariae Lobatae radix flavonoids and puerarin alleviate alcoholic liver injury in zebrafish by regulating alcohol and lipid metabolism

Exessive drinking is commonly associated with a wide spectrum of liver injuries. The term alcoholic liver disease (ALD) is generally used to refer to this spectrum of hepatic abnormalities, and the term hepatic steatosis denotes early lesions. Puerariae Lobatae Radix (PLR) is a common traditional Chinese medicine and has been widely used as an efficient treatment for alcohol-induced damage. Flavonoids are the principal components of PLR that could potentially be responsible for the activation of alcohol metabolism and lipid-lowering effects. However, little is known about the mechanisms underlying their activity against alcoholic injury. In this study, PLR flavonoids (PLF) were obtained by microwave extraction. A 2% ethanol solution was used to establish a model of alcoholic fatty liver disease by exposure of zebrafish larvae for 32 h, and then the zebrafish were administered PLF and puerarin. The results showed that PLF and puerarin significantly decreased lipid accumulation and the levels of total cholesterol and triglycerides in zebrafish larvae. Moreover, PLF and puerarin downregulated the expression of genes related to alcohol and lipid metabolism (CYP2y3, CYP3a65, ADH8a, ADH8b, HMGCRB, and FASN), endoplasmic reticulum stress, and DNA damage (CHOP, EDEM1, GADD45αa, and ATF6) and reduced levels of inflammatory factors (IL-1β, TNF-α) in zebrafish larvae. PLF and puerarin increased the phosphorylation of AMP-activated protein kinase-α (AMPKα) and decreased the total protein level of ACC1. The findings suggested that PLF and puerarin alleviated alcohol-induced hepatic steatosis in zebrafish larvae by regulating alcohol and lipid metabolism, which was closely related to the regulation of the AMPKα-ACC signaling pathway. In conclusion, the study provided a possible therapeutic drug for ALD treatment.

Short-term Cudrania tricuspidata fruit vinegar administration attenuates obesity in high-fat diet-fed mice by improving fat accumulation and metabolic parameters

Previous studies have suggested that vinegar intake can help to reduce body fat and hyperglycemia. Therefore, this study aimed to evaluate the anti-obesity efficacy of vinegar fermented using Cudrania tricuspidata fruits (CTFV) and its main phenolic constituents and to analyze its molecular mechanism and changes in obesity-related metabolizing enzymatic activities. We found that HFD significantly caused hepatic steatosis; increases in body fats, feed efficiency, liver mass, lipids, insulin, oxidative parameters, cardiovascular-associated risk indices, lipase and α-amylase activities, whereas CTFV efficaciously attenuated HFD-induced oxidant stress, fat accumulation, obesity-related enzymatic activity, and the activation or reduction of obesity-related molecular reactions via improving metabolic parameters including phosphorylated insulin receptor substrate 1, protein tyrosine phosphatase 1B, phosphorylated phosphoinositide 3-kinase/protein kinase B, phosphorylated mitogen-activated protein kinases, sterol regulatory element-binding protein 1c, CCAAT/enhancer-binding protein, and fatty acid synthase; and decreases in adiponectin receptor 1, leptin receptor, adenosine monophosphate-activated protein kinase, acetyl-CoA carboxylase, and peroxisome proliferator-activated receptor, subsequently ameliorating HFD-induced obesity. Therefore, CTFV might provide a functional food resource or nutraceutical product for reducing body fat accumulation.

Zebrafish: An emerging model system to study liver diseases and related drug discovery

The zebrafish has emerged as a powerful vertebrate model for studying liver-associated disorders. Liver damage is a crucial problem in the process of drug development and zebrafish have proven to be an important tool for the high-throughput screening of drugs for hepatotoxicity. Although the structure of the zebrafish liver differs to that of mammals, the fundamental physiologic processes, genetic mutations and manifestations of pathogenic responses to environmental insults exhibit much similarity. The larval transparency of the zebrafish is a great advantage for real-time imaging in hepatic studies. The zebrafish has a broad spectrum of cytochrome P450 enzymes, which enable the biotransformation of drugs via similar pathways as mammals, including oxidation, reduction and hydrolysis reactions. In the present review, we appraise the various drugs, chemicals and toxins used to study liver toxicity in zebrafish and their similarities to the rodent models for liver-related studies. Interestingly, the zebrafish has also been effectively used to study the pathophysiology of nonalcoholic and alcoholic fatty liver disease. The genetic models of liver disorders and their easy manipulation provide great opportunity in the area of drug development. The zebrafish has proven to be an influential model for the hepatic system due to its invertebrate-like advantages coupled with its vertebrate biology. The present review highlights the pivotal role of zebrafish in bridging the gap between cell-based and mammalian models.

Herbal Medicine in the Treatment of Non-Alcoholic Fatty Liver Diseases-Efficacy, Action Mechanism, and Clinical Application

Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disease with high prevalence in the developed countries. NAFLD has been considered as one of the leading causes of cryptogenic cirrhosis and chronic liver disease. The individuals with obesity, insulin resistance and diabetes mellitus, hyperlipidaemia, and hypertension cardiovascular disease have a high risk to develop NAFLD. The related critical pathological events are associated with the development of NAFLD including insulin resistance, lipid metabolism dysfunction, oxidative stress, inflammation, apoptosis, and fibrosis. The development of NAFLD range from simple steatosis to non-alcoholic steatohepatitis (NASH). Hepatic steatosis is characterized by fat accumulation, which represents the early stage of NAFLD. Then, inflammation triggered by steatosis drives early NAFLD progression into NASH. Therefore, the amelioration of steatosis and inflammation is essential for NAFLD therapy. The herbal medicine have taken great effects on the improvement of steatosis and inflammation for treating NAFLD. It has been found out that these effects involved the multiple mechanisms underlying lipid metabolism and inflammation. In this review, we pay particular attention on herbal medicine treatment and make summary about the research of herbal medicine, including herb formula, herb extract and naturals compound on NAFLD. We make details about their protective effects, the mechanism of action involved in the amelioration steatosis and inflammation for NAFLD therapy as well as the clinical application.

A Candidate Drug for Nonalcoholic Fatty Liver Disease: A Review of Pharmacological Activities of Polygoni Multiflori Radix

Nonalcoholic fatty liver disease, a type of metabolic syndrome, continues to rise globally. Currently, there is no approved drug for its treatment. Improving lifestyle and exercise can alleviate symptoms, but patients' compliance is poor. More and more studies have shown the potential of Polygoni Multiflori Radix (PMR) in the treatment of NAFLD and metabolic syndrome. Therefore, this paper reviews the pharmacological effects of PMR and its main chemical components (tetrahydroxystilbene glucoside, emodin, and resveratrol) on NAFLD. PMR can inhibit the production of fatty acids and promote the decomposition of triglycerides, reduce inflammation, and inhibit the occurrence of liver fibrosis. At the same time, it maintains an oxidation equilibrium status in the body, to achieve the therapeutic purpose of NAFLD and metabolic syndrome. Although more standardized studies and clinical trials are needed to confirm its efficacy, PMR may be a potential drug for the treatment of NAFLD and its complications. However, the occurrence of adverse reactions of PMR has affected its extensive clinical application. Therefore, it is necessary to further study its toxicity mechanism, enhance efficacy and control toxicity, and even reduce toxicity, which will contribute to the safe clinical use of PMR.

Gastrodin Ameliorates Acute Rejection via IRE1α/TRAF2/NF-κB in Rats Receiving Liver Allografts

Background

Liver transplantation (LT) is currently an effective treatment for end-stage liver disease, but the occurrence of acute rejection (AR) is still the main problem to be solved. The present study aimed to evaluate the effect of gastrodin (GAS) on LT.

Methods

Rat transplant models were established and divided into SHAM, LT, GAS-L (50 mg/kg GAS), and GAS-H (100 mg/kg GAS) groups. The liver function, inflammatory factors, liver histopathology, survival of rats, number of M2-type macrophages, liver cell apoptosis, and pathway proteins were assayed at 7 days and 14 days after the operations.

Results

With increasing GAS concentrations, liver function, expression of proinflammatory factors in the liver, and expression of M2-type molecules in macrophages were significantly improved, and the survival time of rats was significantly prolonged (P < 0.05). All rats treated with low or high doses of GAS were judged to have nondeterministic acute rejection. Flow cytometry showed that liver cell apoptosis was decreased significantly in the GAS-L and GAS-H groups after GAS administration compared with apoptosis and differentiation in the LT group (P < 0.05). Expression levels of Caspase-3, Bad, and Bax proteins were decreased, and the expression of the antiapoptotic protein Bcl-2 was increased in the GAS-L and GAS-H groups (P < 0.05). Mechanistically, the ERS-related IRE1α/TRAF2/NF-κB pathway was suppressed by GAS, and GAS acted mainly on intrahepatic macrophages to affect AR and reduce ROS production (P < 0.05).

Conclusion

GAS ameliorated AR by inhibiting the IRE1α/TRAF2/NF-κB pathway in LT.

Gastrodin relieves inflammation injury induced by lipopolysaccharides in MRC-5 cells by up-regulation of miR-103

The beneficial function of gastrodin towards many inflammatory diseases has been identified. This study designed to see the influence of gastrodin in a cell model of chronic obstructive pulmonary disease (COPD). MRC-5 cells were treated by LPS, before which gastrodin was administrated. The effects of gastrodin were evaluated by conducting CCK-8, FITC-PI double staining, Western blot, qRT-PCR and ELISA. Besides this, the downstream effector and signalling were studied to decode how gastrodin exerted its function. And dual-luciferase assay was used to detect the targeting link between miR-103 and lipoprotein receptor-related protein 1 (LRP1). LPS induced apoptosis and the release of MCP-1, IL-6 and TNF-α in MRC-5 cells. Pre-treating MRC-5 cells with gastrodin attenuated LPS-induced cell damage. Meanwhile, p38/JNK and NF-κB pathways induced by LPS were repressed by gastrodin. miR-103 expression was elevated by gastrodin. Further, the protective functions of gastrodin were attenuated by miR-103 silencing. And LRP1 was a target of miR-103 and negatively regulated by miR-103. The in vitro data illustrated the protective function of gastrodin in LPS-injured MRC-5 cells. Gastrodin exerted its function possibly by up-regulating miR-103 and modulating p38/JNK and NF-κB pathways.

Gastrodin Ameliorates Motor Learning Deficits Through Preserving Cerebellar Long-Term Depression Pathways in Diabetic Rats

Cognitive dysfunction is a very severe consequence of diabetes, but the underlying causes are still unclear. Recently, the cerebellum was reported to play an important role in learning and memory. Since long-term depression (LTD) is a primary cellular mechanism for cerebellar motor learning, we aimed to explore the role of cerebellar LTD pathways in diabetic rats and the therapeutic effect of gastrodin. Diabetes was induced by a single injection of streptozotocin into adult Sprague-Dawley rats. Motor learning ability was assessed by a beam walk test. Pathological changes of the cerebellum were assessed by Hematoxylin-Eosin (HE) and Nissl staining. Cellular apoptosis was assessed by anti-caspase-3 immunostaining. Protein expression levels of LTD pathway-related factors, including GluR2, protein kinase C (PKC), NR2A, and nNOS, in the cerebellar cortex were evaluated by western blotting and double immunofluorescence. The NO concentration was measured. The cellular degeneration and the apoptosis of Purkinje cells were evident in the cerebellum of diabetic rats. Protein expression levels of GluR2 (NC9W: 1.26 ± 0.12; DM9W + S: 0.81 ± 0.07), PKC (NC9W: 1.66 ± 0.10; DM9W + S: 0.58 ± 0.19), NR2A (NC9W: 1.40 ± 0.05; DM9W + S: 0.63 ± 0.06), nNOS (NC9W: 1.26 ± 0.12; DM9W + S: 0.68 ± 0.04), and NO (NC9W: 135.61 ± 31.91; DM9W + S: 64.06 ± 24.01) in the cerebellum were significantly decreased in diabetic rats. Following gastrodin intervention, the outcome of motor learning ability was significantly improved (NC9W: 6.70 ± 3.31; DM9W + S: 20.47 ± 9.43; DM9W + G: 16.04 ± 7.10). In addition, degeneration and apoptosis were ameliorated, and this was coupled with the elevation of the protein expression of the abovementioned biomarkers. Arising from the above, we concluded that gastrodin may contribute to the improvement of motor learning by protecting the LTD pathways in Purkinje cells.