Dendrobium officinale Kimura et Migo attenuates diabetic cardiomyopathy through inhibiting oxidative stress, inflammation and fibrosis in streptozotocin-induced mice

Anti-Inflammatory Therapeutic Mechanisms of Isothiocyanates: Insights from Sulforaphane

Isothiocyanates (ITCs) belong to a group of natural products that possess a highly reactive electrophilic -N=C=S functional group. They are stored in plants as precursor molecules, glucosinolates, which are processed by the tyrosinase enzyme upon plant tissue damage to release ITCs, along with other products. Isolated from broccoli, sulforaphane is by far the most studied antioxidant ITC, acting primarily through the induction of a transcription factor, the nuclear factor erythroid 2-related factor 2 (Nrf2), which upregulates downstream antioxidant genes/proteins. Paradoxically, sulforaphane, as a pro-oxidant compound, can also increase the levels of reactive oxygen species, a mechanism which is attributed to its anticancer effect. Beyond highlighting the common pro-oxidant and antioxidant effects of sulforaphane, the present paper was designed to assess the diverse anti-inflammatory mechanisms reported to date using a variety of in vitro and in vivo experimental models. Sulforaphane downregulates the expression of pro-inflammatory cytokines, chemokines, adhesion molecules, cycloxyhenase-2, and inducible nitric oxide synthase. The signalling pathways of nuclear factor κB, activator protein 1, sirtuins 1, silent information regulator sirtuin 1 and 3, and microRNAs are among those affected by sulforaphane. These anti-inflammatory actions are sometimes due to direct action via interaction with the sulfhydryl structural moiety of cysteine residues in enzymes/proteins. The following are among the topics discussed in this paper: paradoxical signalling pathways such as the immunosuppressant or immunostimulant mechanisms; crosstalk between the oxidative and inflammatory pathways; and effects dependent on health and disease states.

MicroRNAs regulating signaling pathways in cardiac fibrosis: potential role of the exercise training

Cardiovascular and metabolic diseases such as hypertension, type 2 diabetes, and obesity develop long-term fibrotic processes in the heart, promoting pathological cardiac remodeling, including after myocardial infarction, reparative fibrotic processes also occur. These processes are regulated by many intracellular signaling pathways that have not yet been completely elucidated, including those associated with microRNA (miRNA) expression. miRNAs are small RNA transcripts (18-25 nucleotides in length) that act as posttranscriptionally regulators of gene expression, inhibiting or degrading one or more target messenger RNAs (mRNAs), and proven to be involved in many biological processes such as cell cycle, differentiation, proliferation, migration, and apoptosis, directly affecting the pathophysiology of several diseases, including cardiac fibrosis. Exercise training can modulate the expression of miRNAs and it is known to be beneficial in various cardiovascular diseases, attenuating cardiac fibrosis processes. However, the signaling pathways modulated by the exercise associated with miRNAs in cardiac fibrosis were not fully understood. Thus, this review aims to analyze the expression of miRNAs that modulate signaling pathways in cardiac fibrosis processes that can be regulated by exercise training.

Chemical Constituents, Bioactivities, and Pharmacological Mechanisms of Dendrobium officinale: A Review of the Past Decade

Dendrobium officinale, a plant in the Orchidaceae family, has been used in traditional Chinese medicine for thousands of years. Sweet and slightly cold in nature, it can invigorate the stomach, promote fluid production, nourish Yin, and dissipate heat. Over the past decade, more than 60 compounds have been derived from D. officinale, including flavonoids, bibenzyl, and phenanthrene. Various studies have explored the underlying pharmacological mechanisms of these compounds, which have shown antitumor, hypoglycemic, hypertensive, gastrointestinal-regulatory, visceral organ protection, antiaging, and neurorestorative effects. This paper presents a systematic review of the structural classification, biological activity, and pharmacological mechanisms of different chemical components obtained from D. officinale over the past decade. This review aims to provide a reference for future study and establish a foundation for clinical applications. Furthermore, this review identifies potential shortcomings in current research as well as potential directions and methodologies in future plant research.

Efficacy of traditional Chinese medicine on diabetic cardiomyopathy in animal models: a systematic review and meta-analysis

Background: Diabetic cardiomyopathy (DCM) is a severe complication of diabetes that can diminish the quality of life in patients and is a leading cause of death. Research has demonstrated the effectiveness of Traditional Chinese Medicine (TCM) in reducing blood sugar levels and protecting cardiovascular function in both animal models and clinical research studies. Nevertheless, the efficacy of TCM in animal models of DCM has not been analyzed systematically. Method: We searched the following electronic bibliographic databases: Web of Science, PubMed, Cochrane Library, and CNKI(China National Knowledge Infrastructure). Studies that reported the efficacy of TCM in animals with DCM were included. The literature search was conducted using the terms. The data will be restricted from the year 2013 to 24 April 2023, 24 studies were included in the meta-analysis. Result: A total of 24 Traditional Chinese Medicine interventions and 2157 animals met the inclusion criteria. The pooled data revealed that TCM interventions resulted in significant improvements in body weight (BW), heart weight (HW) to body weight ratio (HW/BW), triglyceride (TG) and cholesterol (TC) levels, ejection fraction (EF), fractional shortening (FS) and E/A ratio. Subgroup analysis and meta-regression revealed that the type of TCM, duration of intervention, method of modeling, and animal species were potential sources of heterogeneity. Conclusion: TCM interventions were associated with significant improvements in body weight, heart weight to body weight ratio, triglyceride and cholesterol levels, left ventricular internal dimension in systole, ejection fraction, fractional shortening and E/A ratio. The heterogeneity in the results was found to be potentially due to the type of TCM, duration of intervention, method of modeling, and animal species, as shown in subgroup analysis and meta-regression. Systematic Review Registration: identifier CRD42023402908.

Aloe-Emodin Derivative, an Anthraquinone Compound, Attenuates Pyroptosis by Targeting NLRP3 Inflammasome in Diabetic Cardiomyopathy

Diabetic cardiomyopathy (DCM) is widely recognized as a major contributing factor to the development of heart failure in patients with diabetes. Previous studies have demonstrated the potential benefits of traditional herbal medicine for alleviating the symptoms of cardiomyopathy. We have chemically designed and synthesized a novel compound called aloe-emodin derivative (AED), which belongs to the aloe-emodin (AE) family of compounds. AED was formed by covalent binding of monomethyl succinate to the anthraquinone mother nucleus of AE using chemical synthesis techniques. The purpose of this study was to investigate the effects and mechanisms of AED in treating DCM. We induced type 2 diabetes in Sprague-Dawley (SD) rats by administering a high-fat diet and streptozotocin (STZ) injections. The rats were randomly divided into six groups: control, DCM, AED low concentration (50 mg/kg/day), AED high concentration (100 mg/kg/day), AE (100 mg/kg/day), and positive control (glyburide, 2 mg/kg/day) groups. There were eight rats in each group. The rats that attained fasting blood glucose of ˃16.7 mmol/L were considered successful models. We observed significant improvements in cardiac function in the DCM rats with both AED and AE following four weeks of intragastric treatment. However, AED had a more pronounced therapeutic effect on DCM compared to AE. AED exhibited an inhibitory effect on the inflammatory response in the hearts of DCM rats and high-glucose-treated H9C2 cells by suppressing the pyroptosis pathway mediated by the nucleotide-binding oligomerization domain (NOD)-like receptor pyrin domain 3 (NLRP3) inflammasome. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of differentially expressed genes showed a significant enrichment in the NOD-like receptor signaling pathway compared to the high-glucose group. Furthermore, overexpression of NLRP3 effectively reversed the anti-pyroptosis effects of AED in high-glucose-treated H9C2 cells. This study is the first to demonstrate that AED possesses the ability to inhibit myocardial pyroptosis in DCM. Targeting the pyroptosis pathway mediated by the NLRP3 inflammasome could provide a promising therapeutic strategy to enhance our understanding and treatment of DCM.

Traditional uses, chemical compositions and pharmacological activities of Dendrobium: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Dendrobium is a kind of medicine food homology plant. Dendrobium has long been used to strengthen "Yin" and tonify five viscera.

AIM OF THIS REVIEW

This paper presents a systematic review of the folk usage, chemical composition and pharmacological activity of Dendrobium, aiming to provide a reference for subsequent in-depth understanding and better exploitation of health food, medicine, and natural products.

MATERIALS AND METHODS

Available information about the genus Dendrobium was collected via Web of Science, PubMed, Science Direct, Scopus, APA-Psy Articles, Google Scholar, Connected Papers, Springer Search, and KNCI. The keywords for this article are Dendrobium, traditional use, chemical diversity and pharmacological activity. Use the "Dictionary of Chinese Ethnic Medicine" to provide 23 kinds of Dendrobium with medicinal value, the Latin name of Dendrobium is verified by the Flora of China (www.iplant.cn), and its species distribution and related information are collected.

RESULTS

There are 78 species of Dendrobium in China, 14 of which are endemic to China. At present, 450 compounds including sesquiterpenoids, lignans compounds, phenolic compounds, phenanthrene compounds, bibenzyls, polysaccharides and flavonoids have been isolated and identified from at least 50 species of Dendrobium. Among them, bibenzyls and polysaccharides are the main active components, phenolics and lignans are widely distributed, sesquiterpenes are the most common chemical constituents in genus Dendrobium plants. The most popular research objects are Dendrobium officinale and Dendrobium huoshanense.

CONCLUSIONS

Based on traditional folk uses, chemical composition and pharmacological studies, Dendrobium is considered a promising medicinal and edible plant with multiple pharmacological activities. In addition, a large number of clinical applications and further studies on single chemical components based on the diversity of chemical structures should be conducted, which will lay the foundation for the scientific utilization of genus Dendrobium.

Polysaccharides Extracted from Dendrobium officinale Grown in Different Environments Elicit Varying Health Benefits in Caenorhabditis elegans

Dendrobium officinale is one of the most widely used medicinal herbs, especially in Asia. In recent times, the polysaccharide content of D. officinale has garnered attention due to the numerous reports of its medicinal properties, such as anticancer, antioxidant, anti-diabetic, hepatoprotective, neuroprotective, and anti-aging activities. However, few reports of its anti-aging potential are available. Due to high demand, the wild D. officinale is scarce; hence, alternative cultivation methods are being employed. In this study, we used the Caenorhabditis elegans model to investigate the anti-aging potential of polysaccharides extracted from D. officinale (DOP) grown in three different environments; tree (TR), greenhouse (GH), and rock (RK). Our findings showed that at 1000 µg/mL, GH-DOP optimally extended the mean lifespan by 14% and the maximum lifespan by 25% (p < 0.0001). TR-DOP and RK-DOP did not extend their lifespan at any of the concentrations tested. We further showed that 2000 µg/mL TR-DOP, GH-DOP, or RK-DOP all enhanced resistance to H₂O₂-induced stress (p > 0.05, p < 0.01, and p < 0.01, respectively). In contrast, only RK-DOP exhibited resistance (p < 0.01) to thermal stress. Overall, DOP from the three sources all increased HSP-4::GFP levels, indicating a boost in the ability of the worms to respond to ER-related stress. Similarly, DOP from all three sources decreased α-synuclein aggregation; however, only GH-DOP delayed β-amyloid-induced paralysis (p < 0.0001). Our findings provide useful information on the health benefits of DOP and also provide clues on the best practices for cultivating D. officinale for maximum medicinal applications.

Modern interpretation of the traditional application of Shihu - A comprehensive review on phytochemistry and pharmacology progress of Dendrobium officinale

ETHNOPHARMACOLOGICAL RELEVANCE

The traditional Chinese medicine (TCM) "Shihu" has a long history of medicinal use in China from some species of Dendrobium. D. officinale is a major source of "Shihu" and is widely cultivated in south of China and listed separately as "Tiepi Shihu" by the Chinese Pharmacopoeia in now time. Traditionally, D. officinale has been widely used in daily health care and the treatment of diabetes and gastrointestinal diseases.

AIM OF THIS REVIEW

In order to better develop and utilize D. officinale, we conducted this systematic review of previous studies, showed clear structure of all isolates from D. officinale together with pharmacological progress, hoping to provide references for further research and utilization. In addition, specific display of the chemical components and the research progress of related activities can help to better understand the traditional records and modern pharmaceutical applications of the plant medicine.

MATERIALS AND METHODS

Information on phytochemistry and pharmacological studies of D. officinale was collected from various scientific databases including Web of Science, SciFinder, ACS, Springer, Scopus, PubMed, ScienceDirect, Google Scholar and CNKI.

RESULTS

More than 180 compounds isolated from D. officinale, including bibenzyls, phenols, phenylpropanoids, lignans, flavonoids and polysaccharides are listed in this review. Furthermore, modern pharmacological researches such as hypoglycemia, immune regulation, antioxidant, cardiovascular regulation and gastrointestinal protection are summarized.

CONCLUSION

Based on the summary of the research work of D. officinale, we systematically show the chemical composition of the plant, and concluded the relationship of those composition with plant habitat together with the relationship between the structure of chemical components and pharmacological activity. Moreover, we suggest that some of small molecule compounds could also be quality control of D. officinale besides polysaccharides.

The effects of resveratrol and melatonin on biochemical and molecular parameters in diabetic old female rat hearts

The roles of melatonin and resveratrol-enhanced activation of SIRT1 (silent information regulator 1), GLUT4 (glucose transporter type 4), and PGC-1α (peroxisome proliferator-activated receptor gamma coactivator 1-alpha) in mediating the protective effects on the heart in aged female rats with streptozotocin-induced diabetes were investigated. 16-month-old 48 Wistar female rats were separated into 8 groups with equal numbers. Group 1: Control, Group 2: Resveratrol Control, Group 3: Melatonin Control, Group 4: Resveratrol and Melatonin Control, Group 5: Diabetes, Group 6: Diabetes Resveratrol, Group 7: Diabetes Melatonin, Group 8: Diabetes Resveratrol and Melatonin. A single dose of 40 mg/kg intraperitoneal streptozotocin was injected into the rats of Groups 5, 6, 7, and 8 to induce experimental diabetes. Blood glucose levels were measured from the tail veins of the animals six days after the injections, using a diagnostic glucose kit. Rats with a blood glucose levels ≥300 mg/dl were considered diabetic. 5 mg/kg/day of resveratrol (intraperitoneal) and melatonin (subcutaneous) were administered for four weeks. At the end of the applications, SIRT1, GLUT4, PGC-1α gene expression as well as MDA and GSH levels in the heart tissues were determined by the PCR method from heart tissue samples taken under general anesthesia. The findings of our study show that suppressed antioxidant activity and decreased GLUT4, SIRT1, and PGC-1α gene expression in heart tissue can be reversed by the combination of resveratrol, melatonin, and resveratrol + melatonin in a diabetic aged female rat model. Resveratrol and melatonin supplementation may have a protective effect on cardiac functions in the diabetic aged female rat model.

Bioactivities and Mechanism of Actions of Dendrobium officinale: A Comprehensive Review

Dendrobium officinale has a long history of being consumed as a functional food and medicinal herb for preventing and managing diseases. The phytochemical studies revealed that Dendrobium officinale contained abundant bioactive compounds, such as bibenzyls, polysaccharides, flavonoids, and alkaloids. The experimental studies showed that Dendrobium officinale and its bioactive compounds exerted multiple biological properties like antioxidant, anti-inflammatory, and immune-regulatory activities and showed various health benefits like anticancer, antidiabetes, cardiovascular protective, gastrointestinal modulatory, hepatoprotective, lung protective, and neuroprotective effects. In this review, we summarize the phytochemical studies, bioactivities, and the mechanism of actions of Dendrobium officinale, and the safety and current challenges are also discussed, which might provide new perspectives for its development of drug and functional food as well as clinical applications.

Metabolic accumulation and related synthetic genes of O-acetyl groups in mannan polysaccharides of Dendrobium officinale

Mannan polysaccharides (MPs), which contain substituted O-acetyl groups in their backbone, are abundant in the medicinal plant Dendrobium officinale. Acetyl groups can influence the physiological and biochemical properties of polysaccharides, which mainly accumulate in the stems of D. officinale at four developmental stages (S1-S4), showing an increasing trend and a link with water-soluble polysaccharides (WSPs) and mannose. The genes coding for enzymes that catalyze O-acetyl groups to MPs are unknown in D. officinale. The TRICHOME BIREFRINGENCE-LIKE (TBL) gene family contains TBL and DUF231 domains that can transfer O-acetyl groups to various polysaccharides. Based on an established D. officinale genome database, 37 DoTBL genes were identified. Analysis of cis-elements in the promoter region showed that DoTBL genes might respond to different hormones and abiotic stresses. Most of the genes with MeJA-responsive elements were upregulated or downregulated after treatment with MeJA. qRT-PCR results demonstrated that DoTBL genes had significantly higher expression levels in stems and leaves than in roots. Eight DoTBL genes showed relatively higher expression at S2-S4 stages, which showed a link with the content of WSPs and O-acetyl groups. DoTBL35 and its homologous gene DoTBL34 displayed the higher mRNA level in different organs and developmental stages, which might participate in the acetylation of MPs in D. officinale. The subcellular localization of DoTBL34 and DoTBL35 reveals that the endoplasmic reticulum may play an important role in the acetylation of MPs.

Mechanisms and Active Compounds Polysaccharides and Bibenzyls of Medicinal Dendrobiums for Diabetes Management

BACKGROUND

Medicinal dendrobiums are used popularly in traditional Chinese medicine for the treatment of diabetes, while their active compounds and mechanism remain unclear. This review aimed to evaluate the mechanism and active compounds of medicinal dendrobiums in diabetes management through a systematic approach.

METHODS

A systematic approach was conducted to search for the mechanism and active phytochemicals in Dendrobium responsible for anti-diabetic actions using databases PubMed, Embase, and SciFinder.

RESULTS

Current literature indicates polysaccharides, bibenzyls, phenanthrene, and alkaloids are commonly isolated in Dendrobium genusin which polysaccharides and bibenzyls are most aboundant. Many animal studies have shown that polysaccharides from the species of Dendrobium provide with antidiabetic effects by lowering glucose level and reversing chronic inflammation of T2DM taken orally at 200 mg/kg. Dendrobium polysaccharides protect pancreatic β-cell dysfunction and insulin resistance in liver. Dendrobium polysaccharides up-regulate the abundance of short-chain fatty acid to stimulate GLP-1 secretion through gut microbiota. Bibenzyls also have great potency to inhibit the progression of the chronic inflammation in cellular studies.

CONCLUSION

Polysaccharides and bibenzyls are the major active compounds in medicinal dendrobiums for diabetic management through the mechanisms of lowering glucose level and reversing chronic inflammation of T2DM by modulating pancreatic β-cell dysfunction and insulin resistance in liver as a result from gut microbita regulation.

Protection of CAPE-pNO2 Against Chronic Myocardial Ischemia by the TGF-Β1/Galectin-3 Pathway In Vivo and In Vitro

Although it is known that caffeic acid phenethyl ester (CAPE) and its derivatives could ameliorate acute myocardial injury, their effects on chronic myocardial ischemia (CMI) were not reported. This study aimed to investigate the potential effect of caffeic acid p-nitro phenethyl ester (CAPE-pNO₂, a derivative of CAPE) on CMI and underlying mechanisms. SD rats were subjected to high-fat-cholesterol-diet (HFCD) and vitamin D₃, and the H9c2 cells were treated with LPS to establish CMI model, followed by the respective treatment with saline, CAPE, or CAPE-pNO₂. In vivo, CAPE-pNO₂ could reduce serum lipid levels and improve impaired cardiac function and morphological changes. Data of related assays indicated that CAPE-pNO₂ downregulated the expression of transforming growth factor-β1 (TGF-β1) and galectin-3 (Gal-3). Besides, CAPE-pNO₂ decreased collagen deposition, the number of apoptotic cardiomyocytes, and some related downstream proteins of Gal-3 in the CMI rats. Interestingly, the effects of CAPE-pNO₂ on TGF-β1, Gal-3, and other proteins expressed in the lung were consistent with that in the heart. In vitro, CAPE-pNO₂ could attenuate the fibrosis, apoptosis, and inflammation by activating TGF-β1/Gal-3 pathway in LPS-induced H9c2 cell. However, CAPE-pNO₂-mediated cardioprotection can be eliminated when treated with modified citrus pectin (MCP, an inhibitor of Gal-3). And in comparison, CAPE-pNO₂ presented stronger effects than CAPE. This study indicates that CAPE-pNO₂ may ameliorate CMI by suppressing fibrosis, inflammation, and apoptosis via the TGF-β1/Gal-3 pathway in vivo and in vitro.

Multi-Pharmaceutical Activities of Chinese Herbal Polysaccharides in the Treatment of Pulmonary Fibrosis: Concept and Future Prospects

Pulmonary fibrosis is a fatal chronic progressive respiratory disease, characterized by continuous scarring of the lung parenchyma, leading to respiratory failure and death. The incidence of PF has increased over time. There are drugs, yet, there are some limitations. Hence, it is of importance to find new therapies and new drugs to replace the treatment of pulmonary fibrosis. In recent years, there have been a great number of research reports on the treatment of traditional Chinese medicine polysaccharides in various system fields. Among them, the treatment of PF has also gained extensive attention. This review summarized the source of polysaccharides, the drug activity of traditional Chinese medicine, and the protective effects on targets of Pulmonary fibrosis. We hope it can inspire researchers to design and develop polysaccharides, serving as a reference for potential clinical therapeutic drugs.

Traditional Uses, Phytochemistry, Pharmacology, and Quality Control of Dendrobium officinale Kimura et. Migo

Dendrobium officinale, a well-known plant used as a medicinal and food homologous product, has been reported to contain various bioactive components, such as polysaccharides, bibenzyls, phenanthrenes, and flavonoids. It is also widely used as a traditional medicine to strengthen “Yin”, nourish heart, tonify five viscera, remove arthralgia, relieve fatigue, thicken stomach, lighten body, and prolong life span. These traditional applications are in consistent with modern pharmacological studies, which have demonstrated that D. officinale exhibits various biological functions, such as cardioprotective, anti-tumor, gastrointestinal protective, anti-diabetes, immunomodulatory, anti-aging, and anti-osteoporosis effects. In this review, we summarize the research progress of D. officinale from November 2016 to May 2021 and aim to better understand the botany, traditional use, phytochemistry, and pharmacology of D. officinale, as well as its quality control and safety. This work presents the development status of D. officinale, analyzes gaps in the current research on D. officinale, and raises the corresponding solutions to provide references and potential directions for further studies of D. officinale.

Therapeutic effects of Chinese herbal medicines and their extracts on diabetes

With the improvement of people's living standards and changes in the environment, the incidence of diabetes has increased rapidly. It has gradually become one of the main diseases threatening the health and life of modern people, bringing a great burden to the society. Although the existing treatment methods can effectively control the symptoms of diabetes and delay its progression, they have not brought satisfactory improvement in the quality of life and treatment of patients. Traditional Chinese herbal medicines and their extracts combine thousands of years of experience and the scientific basis provided by modern experimental research, which is expected to bring a qualitative leap in the clinical management of diabetes. Therefore, this article systematically reviews studies on the effects of Chinese herbal medicine and its extracts on diabetes and its complications, and aims to bring new ideas and options for the clinical treatment of diabetes.

Traditional Chinese medicine as a therapeutic option for cardiac fibrosis: Pharmacology and mechanisms

Cardiovascular diseases are one of the leading causes of death worldwide and cardiac fibrosis is a common pathological process for cardiac remodeling in cardiovascular diseases. Cardiac fibrosis not only accelerates the deterioration progress of diseases but also becomes a pivotal contributor for futile treatment in clinical cardiovascular trials. Although cardiac fibrosis is common and prevalent, effective medicines to provide sufficient clinical intervention for cardiac fibrosis are still unavailable. Traditional Chinese medicine (TCM) is the natural essence experienced boiling, fry, and other processing methods, including active ingredients, extracts, and herbal formulas, which have been applied to treat human diseases for a long history. Recently, research has increasingly focused on the great potential of TCM for the prevention and treatment of cardiac fibrosis. Here, we aim to clarify the identified pro-fibrotic mechanisms and intensively summarize the application of TCM in improving cardiac fibrosis by working on these mechanisms. Through comprehensively analyzing, TCM mainly regulates the following pathways during ameliorating cardiac fibrosis: attenuation of inflammation and oxidative stress, inhibition of cardiac fibroblasts activation, reduction of extracellular matrix accumulation, modulation of the renin-angiotensin-aldosterone system, modulation of autophagy, regulation of metabolic-dependent mechanisms, and targeting microRNAs. We also discussed the deficiencies and the development direction of anti-fibrotic therapies on cardiac fibrosis. The data reviewed here demonstrates that TCM shows a robust effect on alleviating cardiac fibrosis, which provides us a rich source of new drugs or drug candidates. Besides, we also hope this review may give some enlightenment for treating cardiac fibrosis in clinical practice.

Current advances of Dendrobium officinale polysaccharides in dermatology: a literature review

Context

Dendrobium officinale Kimura et Migo (Orchidaceae) is a naturally occurring precious traditional Chinese medicine (TCM) originally used in treating yin-deficiency diseases. The main active substances of Dendrobium officinale are polysaccharides (DOP). Recent findings highlighted the potential of DOP as a promising natural material for medical use with a diversity of pharmaceutical effects.

Objective

In this review, we provide a systematic discussion of the current development and potential pharmacological effects of Dendrobium officinale polysaccharides in dermatology.

Methods

English and Chinese literature from 1987 to 2019 indexed in databases including PubMed, PubMed Central, Web of Science, ISI, Scopus and CNKI (Chinese) was used. Dendrobium officinale, Dendrobium officinale polysaccharides, phytochemistry, chemical constituents, biological activities, and pharmacological activities were used as the key words.

Results

Dendrobium officinale polysaccharides have been found to possess hair growth promoting, skin moisturising and antioxidant effects, which are highly valued by doctors and cosmetic engineers. We highlighted advances in moisturising and antioxidant properties from in vivo and in vitro studies. Dendrobium officinale polysaccharides exhibited strong antioxidant effects by decreasing free radicals, enhancing antioxidant system, inhibiting nuclear factor-kappa B and down-regulating inflammatory response.

Conclusions

Our review is a foundation to inspire further research to facilitate the application of Dendrobium officinale polysaccharides in dermatology and promote active research of the use of TCM in dermatology.

Combined treatment with ultrasound-targeted microbubble destruction technique and NM-aFGF-loaded PEG-nanoliposomes protects against diabetic cardiomyopathy-induced oxidative stress by activating the AKT/GSK-3β1/Nrf-2 pathway

The present study sought to investigate the effect of non-mitogenic acidic fibroblast growth factor (NM-aFGF) loaded PEGylated nanoliposomes (NM-aFGF-PEG-lips) combined with the ultrasound-targeted microbubble destruction (UTMD) technique on modulating diabetic cardiomyopathy (DCM)and the mechanism involved. Animal studies showed that the diabetes mellitus (DM) group exhibited typical myocardial structural and functional changes of DCM. The indexes from the transthoracic echocardiography showed that the left ventricular function in the NM-aFGF-PEG-lips + UTMD group was significantly improved compared with the DM group. Histopathological observation further confirmed that the cardiomyocyte structural abnormalities and mitochondria ultrastructural changes were also significantly improved in the NM-aFGF-PEG-lips + UTMD group compared with DM group. The cardiac volume fraction (CVF) and apoptosis index in the NM-aFGF-PEG-lips + UTMD group decreased to 10.31 ± 0.76% and 2.16 ± 0.34, respectively, compared with those in the DM group (CVF = 21.4 ± 2.32, apoptosis index = 11.51 ± 1.24%). Moreover, we also found significantly increased superoxide dismutase (SOD) activity and glutathione peroxidase (GSH-Px) activity as well as clearly decreased lipid hydroperoxide levels and malondialdehyde (MDA) activity in the NM-aFGF-PEG-lips + UTMD group compared with those in the DM group (p < .05). Western blot analysis further revealed the highest level of NM-aFGF, p-AKT, p-GSK-3β1, Nrf-2, SOD2 and NQO1 in the NM-aFGF-PEG-lips + UTMD group. This study confirmed using PEGylated nanoliposomes combined with the UTMD technique can effectively deliver NM-aFGF to the cardiac tissue of diabetic rats. The NM-aFGF can then inhibit myocardial oxidative stress damage due to DM by activating the AKT/GSK/Nrf-2 signaling pathway, which ultimately improved the myocardial structural and functional lesions in diabetic rats.

Combination therapy with semaglutide and rosiglitazone as a synergistic treatment for diabetic retinopathy in rodent animals

OBJECTIVE

To investigate the protective efficacies and potent mechanisms of combination therapy with semaglutide and rosiglitazone (RSG) on the high-glucose incubated human ARPE-19 cells and diabetic retinopathy (DR) model rats.

MAIN METHODS

The CCK-8 methods were used to evaluate the protective effects of semaglutide and RSG alone or combination on the cell viability of high-glucose treated ARPE-19 cells. After the DR rat model was established, the effects of combined treatment on general indexes, retinal morphological changes, retinal Müller cells as well as PI3K/Akt/MTOR related factors of DR model rats were investigated.

RESULTS

The CCK-8 assay showed obviously enhanced protective efficacies of combination therapy with semaglutide and RSG on the ARPE-19 with oxidative stress induced by high-glucose with combination index all below 1.5 demonstrating obvious synergistic effects. Combined incubation could also effectively decrease the expression of inflammatory factors, including TNF-α, IL-1β, IL-6, and the increase of ROS content in ARPE cell culture supernatant induced by high-glucose. Combined use of the antioxidant, PI3K/Akt and mTOR inhibitors, we further demonstrated that combined incubation of semaglutide and RSG could effectively by reduce high glucose-induced inflammatory injury inhibiting ROS/PI3K/Akt/mTOR signaling. Furthermore, chronic combination treatment effectively improved the histopathological characteristics and down-regulated the GFAP expression in Müller cells as well as PI3K/Akt/MTOR signaling pathway-related factors in retina which was better than any monomer treatment group.

CONCLUSIONS

Combined semaglutide with RSG exhibited synergistically protective efficacies on retinal cells by decreasing the GFAP expression, inhibiting oxidative stress and PI3K/Akt/MTOR signaling-transduction in DR model rats.

Modulation effects of Dendrobium officinale on gut microbiota of type 2 diabetes model mice

In recent years, the relationship between type 2 diabetes (T2D) and gut microbiota has attracted much interest. Dendrobium officinale is a valuable traditional Chinese medicine (TCM) with anti-T2D potential, while its action mechanism remains to be further studied. This study was designed to investigate the modulation effects of D. officinale on gut microbiota of T2D model mice to provide clues to its pharmacology by high-throughput sequencing techniques. It was found that D. officinale supplement could significantly reduce the fasting blood glucose levels of T2D mice. Dendrobium officinale supplement could modulate the composition of gut microbiota and increase the relative abundances of key bacterial taxa associated with T2D development, including Akkermansia and Parabacteroides. Compared with placebo group mice, several Kyoto Encyclopedia of Gene and Genomes pathways associated with T2D altered in the D. officinale treated group. These findings indicated the modulation of D. officinale on gut microbiota of T2D mice, which provide potential pharmacological implications.

Dendrobium officinale Attenuates Myocardial Fibrosis via Inhibiting EMT Signaling Pathway in HFD/STZ-Induced Diabetic Mice

Cardiac fibrosis is a major contributor for diabetic cardiomyopathy and Dendrobium officinale possessed therapeutic effects on hyperglycemia and diabetic cardiomyopathy. To further investigate the possible mechanisms of the Dendrobium officinale on diabetic myocardial fibrosis in mice. Water-soluble extracts of Dendrobium officinale (DOE) from dry stem was analyzed by HPLC and phenol-sulfuric acid method. Diabetic mice were induced by intraperitoneal injection of streptozotocin (STZ) (30 mg/kg) for 4 consecutive days after intragastric administration of a high-fat diet (HFD) for 2 weeks. The groups were as follows: control group, model group, DOE low, medium, high dose group (75, 150, 300 mg/kg) and Metformin positive group (125 mg/kg). The results showed that DOE dose-dependently lower serum insulin, total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) and grew the high-density lipoprotein cholesterol (HDL-C) after 12 weeks of daily administration with DOE. Hematoxylin-eosin staining and Sirius red staining showed obvious amelioration of cardiac injury and fibrosis. In addition, the result of immunoblot indicated that DOE increased the expression of peroxisome proliferator activated receptor-α (PPAR-α), phosphorylation of insulin receptor substrate 1 (p-IRS1) and E-cadherin and repressed the expression of transforming growth factor β1 (TGF-β1), phosphorylation of c-Jun N-terminal kinase (p-JNK), Twist, Snail1 and Vimentin. The present findings suggested that DOE ameliorated HFD/STZ-induced diabetic cardiomyopathy (DCM). The possible mechanism mainly associated with DOE accelerating lipid transport, inhibiting insulin resistant and suppressing fibrosis induced by epithelial mesenchymal transition (EMT).

Deciphering the cellular mechanisms underlying fibrosis-associated diseases and therapeutic avenues

Fibrosis is the excessive deposition of extracellular matrix components, which results in disruption of tissue architecture and loss of organ function. Fibrosis leads to high morbidity and mortality worldwide, mainly due to the lack of effective therapeutic strategies against fibrosis. It is generally accepted that fibrosis occurs during an aberrant wound healing process and shares a common pathogenesis across different organs such as the heart, liver, kidney, and lung. A better understanding of the fibrosis-related cellular and molecular mechanisms will be helpful for development of targeted drug therapies. Extensive studies revealed that numerous mediators contributed to fibrogenesis, suggesting that targeting these mediators may be an effective therapeutic strategy for antifibrosis. In this review, we describe a number of mediators involved in tissue fibrosis, including aryl hydrocarbon receptor, Yes-associated protein, cannabinoid receptors, angiopoietin-like protein 2, high mobility group box 1, angiotensin-converting enzyme 2, sphingosine 1-phosphate receptor-1, SH2 domain-containing phosphatase-2, and long non-coding RNAs, with the goal that drugs targeting these important mediators might exhibit a beneficial effect on antifibrosis. In addition, these mediators show profibrotic effects on multiple tissues, suggesting that targeting these mediators will exert antifibrotic effects on different organs. Furthermore, we present a variety of compounds that exhibit therapeutic effects against fibrosis. This review suggests therapeutic avenues for targeting organ fibrosis and concurrently identifies challenges and opportunities for designing new therapeutic strategies against fibrosis.

Recent research progress on natural small molecule bibenzyls and its derivatives in Dendrobium species

Orchidaceous plant Dendrobium genus is often used as a tonic, and its phenolic components have attracted attention for its anti-tumor and anti-diabetic complications. Bibenzyls is one of the essential phenolic active ingredients in the Dendrobium genus. At present, 89 bibenzyl derivatives have been extracted and identified from 46 Dendrobium species. The activity studies have shown that 42 compounds have pharmaceutical activity. Among them, 23 compounds showed antitumor activity; 7 compounds showed anti-diabetes and its complications activity; 10 compounds exhibited neuroprotective effects; 18 compounds showed antioxidant effects; 11 compounds had anti-inflammatory activity; 3 compounds had Antiplatelet aggregation effects; 3 compounds had antibacterial and antiviral effects. The Bibenzyls is small-molecular compounds of natural origin and widely sourced. Previous studies showed that the bibenzyls has good anti-tumor, anti-diabetes and its complications, and neuroprotective effects, and it has great potential for treating tumors, diabetes and its complications, Alzheimer's disease (AD) and Parkinson's disease (PD). Additionally, compounds such as moscatilin (1), gigantol (2) and chrysotoxine (3) have been further studied as lead compounds, and compounds exhibited therapeutical effects had been synthesized. Enough pieces of evidences have shown that the Bibenzyls have good development prospects. This article reviews the pharmacological effects of bibenzyls in Dendrobium species and provides an idea for its further development.

Murine remote ischemic preconditioning suppresses diabetic ketoacidosis by enhancing glycolysis and entry into tricarboxylic acid cycle in the liver

AIMS

Hindlimb ischemia-reperfusion (IR) was previously demonstrated by our group to decrease blood sugar levels by suppressing hepatic gluconeogenesis and enhancing glucose uptake using activation of the parasympathetic nervous system. While IR attenuated hyperglycemia in diabetic mice, it was unclear whether IR regulated energy metabolism in the liver. We investigated the mechanisms by which IR regulates energy metabolism in the liver from type1 diabetic mice.

MAIN METHODS

Streptozotocin-induced diabetic male C57BL/6J mice were used to determine the effect of IR on the factors involved in energy metabolism in the liver (i.e., activation levels of AMP-activated protein kinase, aconitase and pyruvate dehydrogenase; adenosine triphosphate and fumarate concentrations; sirtuin (Sirt) 1 expression). These various signaling pathways and key enzyme activities were examined using western blot analysis and a biochemical technique including a colorimetric assay.

KEY FINDINGS

Under feeding conditions (free access to normal murine chow and water), blood glucose levels and serum ketone body levels were significantly suppressed by IR, whereas phospho-AMP-activated protein kinase and its activity, pyruvate dehydrogenase, aconitase activity, and Sirt 1expression were upregulated. In contrast, peroxisome proliferator-activated receptor γ coactivator-1, which accelerated fatty acid use, was suppressed by IR.

SIGNIFICANCE

These results indicated that in the IR-treated diabetic liver, energy production was promoted through acceleration of the tricarboxylic acid cycle linked with increased glucose preference rather than fatty acid under feeding conditions. Therefore, IR may be beneficial against diabetic hyperglycemia, but also ketoacidosis.

Advances in the Application of Biomimetic Endometrium Interfaces for Uterine Bioengineering in Female Infertility

The Asherman’s syndrome, also known as intrauterine adhesion, often follows endometrium injuries resulting from dilation and curettage, hysteroscopic resection, and myomectomy as well as infection. It often leads to scarring formation and female infertility. Pathological changes mainly include gland atrophy, lack of vascular stromal tissues and hypoxia and anemia microenvironment in the adhesion areas. Surgical intervention, hormone therapy and intrauterine device implantation are the present clinical treatments for Asherman’s syndrome. However, they do not result in functional endometrium recovery or pregnancy rate improvement. Instead, an increasing number of researches have paid attention to the reconstruction of biomimetic endometrium interfaces with advanced tissue engineering technology in recent decades. From micro-scale cell sheet engineering and cell-seeded biological scaffolds to nano-scale extracellular vesicles and bioactive molecule delivery, biomimetic endometrium interfaces not only recreate physiological multi-layered structures but also restore an appropriate nutritional microenvironment by increasing vascularization and reducing immune responses. This review comprehensively discusses the advances in the application of novel biocompatible functionalized endometrium interface scaffolds for uterine tissue regeneration in female infertility.

Physicochemical and Antioxidant Properties of the Degradations of Polysaccharides from Dendrobium officinale and Their Suitable Molecular Weight Range on Inducing HeLa Cell Apoptosis

Different molecular weight polysaccharides of Dendrobium officinale (DOPs) have gradually attracted attention because of their broad biological activities. They, however, remain poorly defined whether their antitumor activity is associated with molecular weight. In this study, the physicochemical, antioxidant, and antitumor properties of DOPs, including the crude polysaccharide (DOP) and its six degradation fractions (DOP1-DOP6) extracted from Dendrobium officinale, were determined. Consequently, DOPs were mainly composed of different ratios of mannose and glucose as follows: 5.15 : 1, 4.62 : 1, 4.19 : 1, 4.46 : 1, 4.32 : 1, 4.29 : 1, and 4.23 : 1, and their molecular weights were significantly different ranging from 652.29 kDa to 11.10 kDa. With the concentration increase of DOPs, the scavenging capacity against OH and DPPH free radicals increased. The antitumor ability of DOPs was different that DOP1-DOP5 (Mw: 176.29 kDa-28.48 kDa) exhibited the best antiproliferation activity than DOP (Mw: 652.29 kDa) and DOP6 (Mw: 11.10 kDa) in HeLa cells rather than PC9, A549, and HepG2 cells. Moreover, it is worth mentioning that DOP1 and DOP5 showed stronger capability on inducing apoptosis of HeLa cells than DOP and DOP6 via the mitochondrial pathway by upregulating the ratio of the Bax/Bal-2 mRNA expression. The results demonstrated that DOPs can be used as the potential natural antioxidant and antitumor products in pharmaceutical industries, and the molecular weight is a crucial influential factor of their antitumor activity that 28.48 kDa-176.29 kDa is a suitable range we may refer to.

Anti-Diabetic Effect of a Shihunine-Rich Extract of Dendrobium loddigesii on 3T3-L1 Cells and db/db Mice by Up-Regulating AMPK-GLUT4-PPARα

The stems of Dendrobium loddigesii, a Chinese herb, are often used to treat diabetes and its polar extract is rich in shihunine, a water-soluble Orchidaceae alkaloid, but little is known about the anti-diabetes effects and mechanism of shihunine. This study investigated the anti-diabetic effect of a shihunine-rich extract of D. loddigesii (DLS) based on 3T3-L1 cells and db/db mice. The underlying mechanisms were primarily explored using Western blot analysis and immunohistochemical staining. The 3T3-L1 cell experiments showed that DLS can reduce the intracellular accumulation of oil droplets as well as triglycerides (p < 0.001) and promote the 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2deoxyglucose (2-NBDG) uptake of 3T3-L1 cells (p < 0.001). The animal experiments confirmed that after 8 weeks of DLS treatment, the body weight, fasting blood sugar, and serum lipid levels of mice were significantly lowered, and the oral glucose tolerance test and serum insulin level were significantly improved compared to the no-treatment diabetes mellitus group. Further histomorphology observation led to the conclusion that the quantities of islet cells were significantly increased and the increase in adipose cell size was significantly suppressed. The immunohistochemical test of pancreatic tissue revealed that DLS inhibited the expression of cleaved cysteine aspartic acid-specific protease 3 (cleaved caspase-3). Western blot experiments showed that DLS had agonistic effects on adenosine monophosphate (AMP)-activated protein kinase phosphorylation (p-AMPK) and increased the expression levels of peroxisome proliferator-activated receptor α (PPARα) and glucose transporter 4 (GLUT4) in liver or adipose tissues. These data suggest that the shihunine-rich extract of D. loddigesii is an anti-diabetic fraction of D. loddigesii. Under our experimental condition, DLS at a dose of 50 mg/kg has good anti-diabetic efficacy.

Dendrobium officinale polysaccharides regulate age-related lineage commitment between osteogenic and adipogenic differentiation

Objectives

Excessive oxidative stress and diminished antioxidant defences could contribute to age‐related tissue damage and various diseases including age‐related osteoporosis. Dendrobium officinale polysaccharides (DOPs), a major ingredient from a traditional Chinese medicine, have a great potential of antioxidative activity. In this study, we explore the role of DOP in age‐related osteoporosis that remains elusive.

Materials and methods

Oxidative stimulation and DOP were used to treat bone marrow mesenchymal stem cells (BMSCs), whose lineage commitment was measured by adipogenic‐ and osteoblastic‐induced differentiation analysis. The oxidative stress and antioxidant capacity of BMSCs under the treatment of DOP were analysed by the level of MDA, SOD. Related mechanism studies were confirmed by qRT‐PCR, Western blotting and siRNA transfection. DOP was orally administrated in aged mice whose phenotype was confirmed by micro‐CT, immunofluorescence, immunochemistry and calcein double‐labelling analysis.

Results

Dendrobium officinale polysaccharide treatment markedly increased osteogenic differentiation of BMSCs, while inhibiting adipogenic differentiation. In vitro, DOP could rescue H2O2‐induced switch of BMSCs differentiation fate. However, this effect was abolished in BMSCs when interfered with Nrf2 siRNA. Furthermore, administration of DOP to aged mice significantly increased the bone mass and reduced the marrow adipose tissue (MAT) accompanied with decreased oxidative stress of BMSCs.

Conclusions

Our study reveals that DOP can attenuate bone loss and MAT accumulation through NRF2 antioxidant signalling, which may represent as potential therapeutic agent for age‐related osteoporosis.

Activation of the PP2A catalytic subunit by ivabradine attenuates the development of diabetic cardiomyopathy

Hyperglycemia-induced apoptosis plays a critical role in the pathogenesis of diabetic cardiomyopathy (DCM). Our previous study demonstrated that ivabradine, a selective I_f current antagonist, significantly attenuated myocardial apoptosis in diabetic mice, but the underlying mechanisms remained unknown. This study investigated the underlying mechanisms by which ivabradine exerts anti-apoptotic effects in experimental DCM. Pretreatment with ivabradine, but not ZD7288 (an established I_f current blocker), profoundly inhibited high glucose-induced apoptosis via inactivation of nuclear factor (NF)-κB signaling in neonatal rat cardiomyocytes. The effect was abolished by transfection of an siRNA targeting protein phosphatase 2A catalytic subunit (PP2Ac). In streptozotocin-induced diabetic mice, ivabradine treatment significantly inhibited left ventricular hyperpolarization-activated cyclic nucleotide-gated channel 2 (HCN2) and HCN4 (major components of the I_f current), activated PP2Ac, and attenuated NF-κB signaling activation and apoptosis, in line with improved histological abnormalities, fibrosis, and cardiac dysfunction without affecting hyperglycemia. These effects were not observed in diabetic mice with virus-mediated knockdown of HCN2 or HCN4 after myocardial injection, but were alleviated by knockdown of PP2Acα. Molecular docking and phosphatase activity assay confirmed direct binding of ivabradine to, and activation of, PP2Ac. In conclusion, ivabradine may directly activate PP2Ac, leading to inhibition of NF-κB signaling activation, myocardial apoptosis, and fibrosis, and eventually improving cardiac function in experimental DCM. Taken together, the present findings suggest that ivabradine may be a promising drug for treatment of DCM.

Fas/FasL-mediated cell death in rat's diabetic hearts involves activation of calcineurin/NFAT4 and is potentiated by a high-fat diet rich in corn oil

This study investigated if calcineurin/nuclear factor of activated T cells (NFAT) axis mediates the cardiac apoptosis in rats with type 1 diabetes mellitus (T1DM)-induced rats or administered chronically high-fat diet rich in corn oil (CO-HFD). Also, it investigated the impact of chronic administration of CO-HFD on Fas/Fas ligand (Fas/FasL)-induced apoptosis in the hearts of T1DM-induced rats. Adult male Wistar rats (140-160 g) were classified as control: (10% fat) CO-HFD: (40% fat), T1DM, and T1DM + CO-HFD (n=20/each). In vitro, cardiomyocytes were cultured in either low glucose (LG) or high glucose (HG) media in the presence or absence of linoleic acid (LA) and other inhibitors. Compared to the control, increased reactive oxygen species (ROS), protein levels of cytochrome C, cleaved caspase-8 and caspase-3, myocardial damage and impeded left ventricular (LV) function were observed in the hearts of all treated groups and maximally in T1DM + CO-HFD-treated rats. mRNA of all NFAT members (NFAT1-4) were not affected by any treatment. CO-HFD or LA significantly up-regulated Fas levels in both LVs and cultured cardiomyocytes in a ROS dependent mechanism and independent of modulating intracellular Ca²⁺ levels or calcineurin activity. T1DM or hyperglycemia significant up-regulated mRNA and protein levels of Fas and FasL by activating Ca²⁺/calcineurin/NFAT-4 axis. Furthermore, Fas/FasL cell death induced by recombinant FasL (rFasL) or HG media was enhanced by pre-incubating the cells with LA. In conclusion, activation of the Ca²⁺/calcineurin/NFAT4 axis is indispensable for hyperglycemia-induced Fas/FasL cell death in the cardiomyocytes and CO-HFD sensitizes this by up-regulation of Fas.

Dendrobium polysaccharides attenuate cognitive impairment in senescence-accelerated mouse prone 8 mice via modulation of microglial activation

Dendrobium is one of the most important traditional Chinese medicinal foods used to treat age-related disorders. However, it remains unclear whether Dendrobium affects the progression of Alzheimer's disease (AD). In the present study, we investigated the effects of Dendrobium officinale polysaccharides (DOP) on the BV2 microglial cell line and the senescence-accelerated mouse prone 8 (SAMP8) mouse strain. In vitro experiments showed that DOP pretreatment contributed to BV2 cells shifting from proinflammatory to anti-inflammatory phenotypes with enhanced Aβ clearance in response to Aβ insults. For the in vivo study, mice were chronically treated with DOP in drinking water from 4 to 7 months of age. The results showed that DOP remarkably attenuated cognitive decline in SAMP8 mice. DOP also inhibited the increased hippocampal microglial activation in SAMP8 mice with downregulation of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), while interleukin-10 (IL-10), neprilysin (NEP) and insulin-degrading enzyme (IDE) were upregulated. The accumulation of hippocampal Aβ42 and phosphated Tau proteins in SAMP8 mice was also reduced. Taken together, our data suggest that Dendrobium has the potential to provide neuroprotection against AD-related cognitive impairment via modulation of microglial activation.

Mechanistic insights into the augmented effect of bone marrow mesenchymal stem cells and thiazolidinediones in streptozotocin-nicotinamide induced diabetic rats

This study was designed to assess whether the protective effects of bone marrow-derived mesenchymal stem cells (MSCs) against diabetes could be enhanced by pioglitazone (PIO), a PPARγ agonist. Combined MSCs and PIO treatments markedly improved fasting blood glucose, body weight, lipid profile levels, insulin level, insulin resistance, β cell function. Those protective effects also attenuated both pancreatic lesions and fibrosis in diabetic rats and decreased the depletion of pancreatic mediators of glycemic and lipid metabolism including peroxisome proliferator-activated receptor alpha (PPARα), PGC-1α, GLP-1 and IRS-2. Cardiac biogenesis of diabetic groups was also improved with MSCs and/or PIO treatments as reflected by the enhanced up-regulation of the expressions of cardiac IRS1, Glucose transporter 4, PGC-1, PPARα and CPT-1 genes and the down-regulated expression of lipogenic gene SREBP. The combination of MSCs and PIO also potentiated the decrease of abnormal myocardial pathological lesions in diabetic rats. Similarly, the inhibitory effects of MSCs on diabetic cardiac fibrosis and on the up regulations of TGF-β, collagen I and III gene expressions were partial but additive when combined with PIO. Therefore, combined therapy with PIO and BMCs transplantation could further potentiate the protective benefit of MSCs against diabetes and cardiac damage compared to MSCs monotherapy.

Dendrobium Officinale Kimura et Migo Ameliorates Insulin Resistance in Rats with Diabetic Nephropathy

BACKGROUND Emerging evidence suggests the potential of Dendrobium officinale Kimura et Migo (DO) in treating the complications of diabetes mellitus (DM). We evaluated the therapeutic potential of DO in treating diabetic nephropathy (DN) by preventing insulin resistance. MATERIAL AND METHODS A DN model was established. Mean glomerular volume of rats was estimated by the method of Weibel-Gomez. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was used to determine the expression of mRNAs and we used Western blot assay to determine the expression of proteins. The levels of fasting insulin (FINS) and glucagon (GLU) were measured and we assessed the levels of high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-a (TNF-a), and interleukin-6 (IL-6) using the enzyme-linked immunosorbent assay (ELISA). RESULTS Compared with the Normal rats, the levels of urinary glucose, albuminuria, Scr, albuminuria/Scr and BUN, and the expression levels of CaN, TLR-2, TLR-4, MyD88, hs-CRP, TNF-a, and IL-6, the level of FINS, GLU, and HOMAIR were increased in DN, DO 1.0, DO 2.0, and DMBG groups. Compared with the DN rats, in DO 1.0, DO 2.0, and DMBG groups the glomerular volume was smaller, the levels of urinary glucose, albuminuria, Scr, albuminuria/Scr, and BUN, the expression levels of CaN, TLR-2, TLR-4, MyD88, hs-CRP, TNF-a, and IL-6, the level of FINS, GLU, and HOMA-IR were decreased. CONCLUSIONS We found that DO prevents insulin resistance in rats with DN. This may be associated with reduction of TLRs and inflammatory response, which should be further verified by loss of DO effects on DN after treatment of inhibitors of TLRs.

Murine remote preconditioning increases glucose uptake and suppresses gluconeogenesis in hepatocytes via a brain-liver neurocircuit, leading to counteracting glucose intolerance

AIMS

Our previous study revealed that cyclic hindlimb ischaemia-reperfusion (IR) activates cardiac acetylcholine (ACh) synthesis through the cholinergic nervous system and cell-derived ACh accelerates glucose uptake. However, the mechanisms regulating glucose metabolism in vivo remain unknown. We investigated the effects and mechanisms of IR in mice under pathophysiological conditions.

METHODS

Using IR-subjected male C57BL/6J mice, the effects of IR on blood sugar (BS), glucose uptake, central parasympathetic nervous system (PNS) activity, hepatic gluconeogenic enzyme expression and those of ACh on hepatocellular glucose uptake were assessed.

RESULTS

IR decreased BS levels by 20% and increased c-fos immunoreactivity in the center of the PNS (the solitary tract and the dorsal motor vagal nucleus). IR specifically downregulated hepatic gluconeogenic enzyme expression and activities (glucose-6-phosphatase and phosphoenolpyruvate carboxykinase) and accelerated hepatic glucose uptake. Transection of a hepatic vagus nerve branch decreased this uptake and reversed BS decrease. Suppressed gluconeogenic enzyme expression was reversed by intra-cerebroventricular administration of a choline acetyltransferase inhibitor. Moreover, IR significantly attenuated hyperglycaemia in murine model of type I and II diabetes mellitus.

CONCLUSIONS

IR provides another insight into a therapeutic modality for diabetes mellitus due to regulating gluconeogenesis and glucose-uptake and advocates an adjunctive mode rectifying disturbed glucose metabolism.

Ursolic acid ameliorates oxidative stress, inflammation and fibrosis in diabetic cardiomyopathy rats

Diabetic cardiomyopathy is a major and severe cardiovascular complication of diabetes mellitus. Ursolic acid, a pentacyclic triterpene compound widespread in fruits and plants, performs a variety of pharmacological activities including lowering blood glucose, anti-oxidation, anti-inflammation and anti-fibrosis. Our present study aimed to investigate the cardioprotective effects of ursolic acid on diabetic cardiomyopathy rats and uncover its underlying mechanism. Diabetes mellitus was induced by a single injection of STZ-only (40 mg/ kg, i.v.) in male SD rats. Animals were divided into three groups (n=10): control group (normal saline, i.g.), diabetic group (normal saline, i.g.) and diabetic+ursolic acid group (35 mg/kg UA + normal saline, i.g.). Rats were administered for 8 weeks from 5th to 12th week. After the last administration, cardiac function was evaluated; HWI was calculated; FBG, CK, LDH in serum and SOD, MDA in cardiac tissue were detected. HE staining and Masson trichrome staining were employed to observe pathological alterations. Immunohistochemistry and western blotting were taken to determine the expression levels of TNF-α, MCP-1, TGF-β1 and MMP-2 in the heart. The results dramatically showed increased levels of FBG, CK, LDH, MDA and a decreased activity of SOD in diabetic group, in which left ventricular dysfunction, cardiac myocytes hypertrophy, inflammatory cell infiltration and myocardial interstitial fibrosis had also been found. What's more, the expressions of TNF-α, MCP-1 and TGF-β1 were significantly up-regulated and the expression of MMP-2 was markedly down-regulated in myocardium. Interestingly, treatment with ursolic acid remarkably ameliorated these changes. Collectively, our study strongly showed that ursolic acid is capable of improving the cardiac structure and function in STZ-induced diabetic cardiomyopathy rats by attenuating oxidative stress, inflammation and fibrosis.

CAPE-pNO2 ameliorated diabetic nephropathy through regulating the Akt/NF-κB/ iNOS pathway in STZ-induced diabetic mice

Diabetic nephropathy (DN) is one of the most severe complications of diabetes mellitus. This study aimed to determine the effects and potential mechanism of caffeic acid para-nitro phenethyl ester (CAPE-pNO₂), a derivative of caffeic acid phenethyl ester (CAPE), on DN; In vivo, intraperitoneal injections of streptozotocin (STZ) were used to induce diabetes in mice; then, the mice were intraperitoneally injected daily with CAPE or CAPE-pNO₂ for 8 weeks. The mice were sacrificed, and blood samples and kidney tissues were collected to measure biological indexes. The results showed that CAPE and CAPE-pNO₂ could lower serum creatinine, blood urea nitrogen, 24-h albumin excretion, malondialdehyde and myeloperoxidase levels and increase superoxide dismutase activity in diabetic mice. According to HE, PAS and Masson staining, these two compounds ameliorated structural changes and fibrosis in the kidneys. In addition, the immunohistochemical and western blot results showed that CAPE and CAPE-pNO₂ inhibited inflammation through the Akt/NF-κB pathway and prevented renal fibrosis through the TGF-β/Smad pathway. In vitro, CAPE and CAPE-pNO₂ inhibited glomerular mesangial cell (GMC) proliferation, arrested cell cycle progression and suppressed ROS generation. These compounds also inhibited ECM accumulation via regulating the TGF-β1, which was a similar effect to that of the NF-κB inhibitor PDTC. More importantly, CAPE and CAPE-pNO₂ could up-regulate nitric oxide synthase expression in STZ-induced diabetic mice and HG-induced GMCs. CAPE-pNO₂ had stronger effects than CAPE both in vivo and in vitro. These data suggest that CAPE-pNO₂ ameliorated DN by suppressing oxidative stress, inflammation, and fibrosis via the Akt/NF-κB/ iNOS pathway.

Dendrobium: Sources of Active Ingredients to Treat Age-Related Pathologies

Dendrobium represents one of the most important orchid genera, ornamentally and medicinally. Dendrobiums are sympodial epiphytic plants, which is a name they are worthy of, the name coming from Greek origin: "dendros", tree, and "bios", life. Dendrobium species have been used for a thousand years as first-rate herbs in traditional Chinese medicine (TCM). They are source of tonic, astringent, analgesic, antipyretic, and anti-inflammatory substances, and have been traditionally used as medicinal herbs in the treatment of a variety of disorders, such as, nourishing the stomach, enhancing production of body fluids or nourishing Yin. The Chinese consider Dendrobium as one of the fifty fundamental herbs used to treat all kinds of ailments and use Dendrobium tonic for longevity. This review is focused on main research conducted during the last decade (2006-2016) on Dendrobium plants and their constituents, which have been subjected to investigations of their pharmacological effects involving anticancer, anti-diabetic, neuroprotective and immunomodulating activities, to report their undeniable potential for treating age-related pathologies.

Temperature-sensitive heparin-modified poloxamer hydrogel with affinity to KGF facilitate the morphologic and functional recovery of the injured rat uterus

Endometrial injury usually results in intrauterine adhesion (IUA), which is an important cause of infertility and recurrent miscarriage in reproductive women. There is still lack of an effective therapeutic strategy to prevent occurrence of IUA. Keratinocyte growth factor (KGF) is a potent repair factor for epithelial tissues. Here, a temperature-sensitive heparin-modified poloxamer (HP) hydrogel with affinity to KGF (KGF-HP) was used as a support matrix to prevent IUA and deliver KGF. The rheology of KGF-HP hydrogel was carefully characterized. The cold KGF-HP solution was rapidly transited to hydrogel with suitable storage modulus (G') and loss modulus (G″) for the applications of uterus cavity at temperature of 33 °C. In vitro release demonstrated that KGF was released from HP hydrogels in sustained release manner for a long time. In vivo bioluminescence imaging showed that KGF-HP hydrogel was able to prolong the retention of the encapsulated KGF in injured uterus of rat model. Moreover, the morphology and function of the injured uterus were significantly recovered after administration of KGF-HP hydrogel, which were evaluated by two-dimensional ultrasound imaging and receptive fertility. Not only proliferation of endometrial glandular epithelial cells and luminal epithelial cells but also angiogenesis of injured uterus were observed by Ki67 and CD31 staining after 7 d of treatment with KGF-HP hydrogel. Finally, a close relatively relationship between autophagy and proliferation of endometrial epithelial cells (EEC) and angiogenesis was firstly confirmed by detecting expression of LC3-II and P62 after KGF treatment. Overall, KGF-HP may be used as a promising candidate for IUA treatment.

Roles and Mechanisms of Herbal Medicine for Diabetic Cardiomyopathy: Current Status and Perspective

Diabetic cardiomyopathy is one of the major complications among patients with diabetes mellitus. Diabetic cardiomyopathy (DCM) is featured by left ventricular hypertrophy, myocardial fibrosis, and damaged left ventricular systolic and diastolic functions. The pathophysiological mechanisms include metabolic-altered substrate metabolism, dysfunction of microvascular, renin-angiotensin-aldosterone system (RAAS) activation, oxidative stress, cardiomyocyte apoptosis, mitochondrial dysfunction, and impaired Ca²⁺ handling. An array of molecules and signaling pathways such as p38 mitogen-activated protein kinase (p38 MAPK), c-Jun N-terminal kinase (JNK), and extracellular-regulated protein kinases (ERK) take roles in the pathogenesis of DCM. Currently, there was no remarkable effect in the treatment of DCM with application of single Western medicine. The myocardial protection actions of herbs have been gearing much attention. We present a review of the progress research of herbal medicine as a potential therapy for diabetic cardiomyopathy and the underlying mechanisms.

An NMR-Based Metabolomic Approach to Unravel the Preventive Effect of Water-Soluble Extract from Dendrobium officinale Kimura & Migo on Streptozotocin-Induced Diabetes in Mice

Dendrobium officinale Kimura & Migo (D. officinale) is a precious herbal medicine. In this study, we investigated metabolic mechanism underlying the effect of D. officinale water extract (DOWE) on diabetes prevention in mice after streptozotocin (STZ) exposure using NMR-based metabolomics. Interestingly, we found a decrease in blood glucose and an increase in liver glycogen in mice pretreated with DOWE after STZ exposure. The DOWE pretreatment significantly increased citrate and glutamine in the serum as well as creatine, alanine, leucine, isoleucine, valine, glutamine, glutathione and taurine in the liver of STZ-treated mice. Furthermore, serum glucose was significantly negatively correlated with citrate, pyruvate, alanine, isoleucine, histidine and glutamine in the serum as well as alanine and taurine in the liver. These findings suggest that the effect of DOWE on diabetes prevention may be linked to increases in liver glycogen and taurine as well as the up-regulation of energy and amino acid metabolism.