Effect of gomisin A on osteoblast differentiation in high glucose-mediated oxidative stress

Schisandra chinensis lignans improve insulin resistance by targeting TLR4 and activating IRS-1/PI3K/AKT and NF-κB signaling pathways

Schisandra chinensis, a traditional Chinese medicine, has been widely applied in China to treat diabetes and its complications. The aim of this study was to discover the active compounds and explain related molecular mechanism contributing to the anti-diabetic effect of Schisandra chinensis. Herein, the therapeutic effects of Schisandra chinensis extracts on type 2 diabetes mellitus (T2DM) were firstly confirmed in vivo. Subsequently, various lignans were isolated from Schisandra chinensis and tested for hypoglycemic activity in palmitic acid-induced insulin-resistant HepG2 (IR-HepG2) cells. Among these lignans, R-biar-(7S,8R)-6,7,8,9-tetrahydro-1,2,3,12,13,14-hexamethoxy-7,8-dimethyl-7-dibenzo [a, c] cyclooctenol (compound 2) and Gomisin A (compound 4) were identified significantly increased the glucose consumption in IR-HepG2 cells. Meanwhile, compounds 2 and 4 activated the insulin receptor substrate-1 (IRS-1)/phosphoinositide 3-kinase (PI3K)/Ak strain transforming (AKT) pathway, which regulates glucose transporter 2 (GLUT2) and glucose-6-phosphatase (G6Pase), essential for gluconeogenesis and glucose uptake. These compounds also inhibited the nuclear factor-κB (NF-κB) signaling pathway, reducing interleukin-6 (IL-6) levels. Importantly, the hypoglycemic effects of compounds 2 and 4 were diminished after Toll-like receptor 4 (TLR4) knockdown. Cellular thermal shift assays confirmed increased TLR4 protein stability upon treatment with these compounds, indicating direct binding to TLR4. Furthermore, TLR4 knockdown reversed the effects of compounds 2 and 4 on the NF-κB and IRS-1/PI3K/AKT pathways. Taken together, compounds 2 and 4 alleviate IR by targeting TLR4, thereby modulating the NF-κB and IRS-1/PI3K/AKT pathways. These findings suggest that compounds 2 and 4 could be developed as therapeutic agents for T2DM.

Analysis of Lignan Content and Rhizosphere Microbial Diversity of Schisandra chinensis (Turcz.) Baill. Resources

Genetic and environmental factors influence the growth and quality of medicinal plants. In recent years, rhizosphere microorganisms have also emerged as significant factors affecting the quality of medicinal plants. This study aimed to identify Schisandra resources with high lignan content and analyze the microbial diversity of the rhizosphere soil. High-performance liquid chromatography was used to measure the lignan content in nine Schisandra fruits. High-throughput sequencing was used to analyze the 16S rDNA sequences of rhizosphere bacteria to identify bacterial species diversity. The total lignan content of the nine Schisandra resources ranged from 9.726 mg/g to 14.031 mg/g, with ZJ27 having the highest content and ZJ25 the lowest. Among the six lignan components, Schisandrol A had the highest content, ranging from 5.133 mg/g to 6.345 mg/g, with a significant difference between ZJ25, ZJ27, and other resources (p < 0.05). Schizandrin C had the lowest content, ranging from 0.062 mg/g to 0.419 mg/g, with more significant differences among the resources. A total of 903,933 sequences were obtained from the rhizosphere soil of the nine Schisandra resources, clustered into 10,437 OTUs at a 97% similarity level. The dominant bacterial phyla were Actinobacteriota, Acidobacteriota, Proteobacteria, Chloroflexi, Gemmatimonadota, and Verrucomicrobiota. The dominant bacterial genera were Candidatus_Udaeobacter, Candidatus_Solibacter, RB41, Bradyrhizobium, Gaiella, and Arthrobacter. ZJ27 is the Schisandra resource with the highest lignan content, and the rhizosphere bacteria of Schisandra are rich in diversity. Schisandra B is negatively correlated with Bryobacter, Candidatus_Solibacter, and unnamed genera of Gaiellales.

Gastrodin improves osteoblast function and adhesion to titanium surface in a high glucose environment

Objective

To investigate the effects of gastrodin on the biological behavior of osteoblasts and osseointegration on the surface of the titanium plate in a high glucose environment, and to explore the possible regulatory mechanisms involved.

Methods

A high glucose-induced oxidative damage model of MC3T3-E1 cells was established in vitro to observe the effects of gastrodin on cellular oxidative stress, cell viability, osteogenic differentiation, mineralization, migration, and adhesion ability on the titanium surface.

Results

High glucose environment can cause oxidative stress damage to MC3T3-E1 cells, leading to a decrease in cell viability, osteogenesis, migration, adhesion and other functions. Gastrodin can upregulate the expression of antioxidant enzymes (Nrf2 and HO-1) and osteogenic differentiation related proteins (RUNX2 and BMP2) in MC3T3-E1 cells in high glucose environment, thereby inhibiting the excessive production of intracellular reactive oxygen species (ROS), reversing the decrease in cell viability, and improving the osteogenic differentiation and mineralization ability of osteoblasts. And gastrodin alleviated the decline in cell migration ability, improved the morphology of the cytoskeleton and increased the adhesion ability of osteoblasts on the surface of titanium plates in high glucose environment. However, gastrodin itself did not affect the cell viability, osteogenic differentiation and mineralization ability of osteoblasts in normal environment.

Conclusions

Gastrodin may protect MC3T3-E1 cells osteogenesis and osseointegration on the surface of the titanium plate in vitro by upregulating antioxidant enzymes expression, and attenuating high glucose-induced oxidative stress. Therefore, gastrodin may be a potential drug to address the problem of poor implant osseointegration in patients with diabetes.

Elucidating the pharmacodynamic mechanisms of Yuquan pill in T2DM rats through comprehensive multi-omics analyses

Background: Yuquan Pill (YQW) is a modern concentrated pill preparation of six herbs, namely, Ge Gen (Pueraria lobata Ohwi), Di huang (Rehmannia glutinosa Libosch.), Tian Huafen (Trichosanthes kirilowii Maxim.), Mai Dong (Ophiopogon japonicus (L. f.) Ker Gawl.), Wu Weizi (Schisandra chinensis (Turcz.) Baill.) and Gan Cao (Glycyrrhiza uralensis Fisch.). It is extensively used to treat type 2 diabetes-related glucose and lipid metabolism disorders. But what's the pharmacodynamic substance and how it works in the treatment of Type 2 diabetes mellitus (T2DM) are still unclear. Purpose: The purpose of this study is to determine the likely pharmacological components and molecular mechanism of YQW's intervention on T2DM by combining serum pharmacochemistry, network analysis and transcriptomics. Methods: The efficacy and prototypical components of blood entry were determined after oral administration of YQW aqueous solution to T2DM rats induced by high-fat feed and low-dose streptozotocin (STZ), and the key targets and pathways for these compounds to intervene in T2DM rats were predicted and integrated using network analysis and transcriptomics techniques. Results: In diabetic rats, YQW can lower TG, CHO, NO, and MDA levels (p < 0.05) while increasing HDL-C levels (p < 0.01), and protecting the liver and kidney. 22 prototype components (including puerarin, daidzein, 3'-methoxypuerarin, and liquiritigenin, among others) were found in the serum of rats after oral administration of YQW for 90 min, which might be used as a possible important ingredient for YQW to intervene in T2DM rats. 538 YQW pharmacodynamic components-related targets and 1,667 disease-related targets were projected through the PharmMapper database, with 217 common targets between the two, all of which were engaged in regulating PI3K-Akt, MAPK, Ras and FoxO signal pathway. Finally, the mRNA expression profiles of liver tissues from rats in the control, model, and YQW groups were investigated using high-throughput mRNA sequencing technology. YQW can regulate the abnormal expression of 89 differential genes in a disease state, including 28 genes with abnormally high expression and 61 genes with abnormally low expression. Five common genes (Kit, Ppard, Ppara, Fabp4, and Tymp) and two extensively used regulatory pathways (PI3K-Akt and MAPK signaling pathways) were revealed by the integrated transcriptomics and network analysis study. Conclusion: The mechanism of YQW's intervention in T2DM rats could be linked to 22 important components like puerarin, daidzein, and glycyrrhetinic acid further activating PI3K-Akt and MAPK signaling pathways by regulating key targets Kit, Ppard, Ppara, Fabp4, and Tymp, and thus improving lipid metabolism disorder, oxidative stress, and inflammation levels in T2DM rats. On the topic, more research into the pharmacological ingredient foundation and mechanism of YQW intervention in T2DM rats can be done.

An analysis of the nutritional effects of Schisandra chinensis components based on mass spectrometry technology

OBJECTIVE

Schisandra chinensis (Turcz.) Baill. (S. chinensis) is a Traditional Chinese medicinal herb that can be used both for medicinal purposes and as a food ingredient due to its beneficial properties, and it is enriched with a wide of natural plant nutrients, including flavonoids, phenolic acids, anthocyanins, lignans, triterpenes, organic acids, and sugars. At present, there is lack of comprehensive study or systemic characterization of nutritional and active ingredients of S. chinensis using innovative mass spectrometry techniques.

METHODS

The comprehensive review was conducted by searching the PubMed databases for relevant literature of various mass spectrometry techniques employed in the analysis of nutritional components in S. chinensis, as well as their main nutritional effects. The literature search covered the past 5 years until March 15, 2023.

RESULTS

The potential nutritional effects of S. chinensis are discussed, including its ability to enhance immunity, function as an antioxidant, anti-allergen, antidepressant, and anti-anxiety agent, as well as its ability to act as a sedative-hypnotic and improve memory, cognitive function, and metabolic imbalances. Meanwhile, the use of advanced mass spectrometry detection technologies have the potential to enable the discovery of new nutritional components of S. chinensis, and to verify the effects of different extraction methods on these components. The contents of anthocyanins, lignans, organic acids, and polysaccharides, the main nutritional components in S. chinensis, are also closely associated to its quality.

CONCLUSION

This review will provide guidelines for an in-depth study on the nutritional value of S. chinensis and for the development of healthy food products with effective components.

Role of Advanced Glycation End-Products and Oxidative Stress in Type-2-Diabetes-Induced Bone Fragility and Implications on Fracture Risk Stratification

Type 2 diabetes (T2D) and osteoporosis (OP) are major causes of morbidity and mortality that have arelevant health and economic burden. Recent epidemiological evidence suggests that both of these disorders are often associated with each other and that T2D patients have an increased risk of fracture, making bone an additional target of diabetes. As occurs for other diabetic complications, the increased accumulation of advanced glycation end-products (AGEs) and oxidative stress represent the major mechanisms explaining bone fragility in T2D. Both of these conditions directly and indirectly (through the promotion of microvascular complications) impair the structural ductility of bone and negatively affect bone turnover, leading to impaired bone quality, rather than decreased bone density. This makes diabetes-induced bone fragility remarkably different from other forms of OP and represents a major challenge for fracture risk stratification, since either the measurement of BMD or the use of common diagnostic algorithms for OP have a poor predictive value. We review and discuss the role of AGEs and oxidative stress on the pathophysiology of bone fragility in T2D, providing some indications on how to improve fracture risk prediction in T2D patients.

The role of mitochondria in the peri-implant microenvironment

NEW FINDINGS

What is the topic of this review? In this review, we consider the key role of mitochondria in the peri-implant milieu, including the regulation of mitochondrial reactive oxygen species and mitochondrial metabolism in angiogenesis, the polarization of macrophage immune responses, and bone formation and bone resorption during osseointegration. What advances does it highlight? Mitochondria contribute to the behaviours of peri-implant cell lines based on metabolic and reactive oxygen species signalling modulations, which will contribute to the research field and the development of new treatment strategies for improving implant success.

ABSTRACT

Osseointegration is a dynamic biological process in the local microenvironment adjacent to a bone implant, which is crucial for implant performance and success of the implant surgery. Recently, the role of mitochondria in the peri-implant microenvironment during osseointegration has gained much attention. Mitochondrial regulation has been verified to be essential for cellular events in osseointegration and as a therapeutic target for peri-implant diseases in the peri-implant microenvironment. In this review, we summarize our current knowledge of the key role of mitochondria in the peri-implant milieu, including the regulation of mitochondrial reactive oxygen species and mitochondrial metabolism in angiogenesis, the polarization of macrophage immune responses, and bone formation and resorption during osseointegration, which will contribute to the research field and the development of new treatment strategies to improve implant success. In addition, we indicate limitations in our current understanding of the regulation of mitochondria in osseointegration and suggest topics for further study.

Mechanism and Prospect of Gastrodin in Osteoporosis, Bone Regeneration, and Osseointegration

Gastrodin, a traditional Chinese medicine ingredient, is widely used to treat vascular and neurological diseases. However, recently, an increasing number of studies have shown that gastrodin has anti-osteoporosis effects, and its mechanisms of action include its antioxidant effect, anti-inflammatory effect, and anti-apoptotic effect. In addition, gastrodin has many unique advantages in promoting bone healing in tissue engineering, such as inducing high hydrophilicity in the material surface, its anti-inflammatory effect, and pro-vascular regeneration. Therefore, this paper summarized the effects and mechanisms of gastrodin on osteoporosis and bone regeneration in the current research. Here we propose an assumption that the use of gastrodin in the surface loading of oral implants may greatly promote the osseointegration of implants and increase the success rate of implants. In addition, we speculated on the potential mechanisms of gastrodin against osteoporosis, by affecting actin filament polymerization, renin-angiotensin system (RAS) and ferroptosis, and proposed that the potential combination of gastrodin with Mg2+, angiotensin type 2 receptor blockers or artemisinin may greatly inhibit osteoporosis. The purpose of this review is to provide a reference for more in-depth research and application of gastrodin in the treatment of osteoporosis and implant osseointegration in the future.

Quercetin ameliorated insulin resistance via regulating METTL3-mediated N6-methyladenosine modification of PRKD2 mRNA in skeletal muscle and C2C12 myocyte cell line

BACKGROUND AND AIMS

N6-Methyladenosine (m6A) modification is involved in many pathological processes, including insulin resistance (IR). Quercetin (Que), a bioactive compound with strong antioxidant activity, has potential therapeutic effects on IR-related metabolic diseases. The aim of this study is to investigate the roles of m6A and Que in hyperinsulinemia.

METHODS AND RESULTS

Male C57Bl/6 mice received a high-fat diet (HFD) for 8 weeks to establish an IR model. Que treatment reduced the body weight, blood glucose, plasma triglycerides (TG) and serum insulin, ameliorated IR, and decreased oxidative stress in HFD-fed mice. Cellular IR model was established in C2C12 cells by palmitic acid (PA) stimulation, and a noncytotoxic dose of Que was found to promote glucose uptake and inhibit oxidative stress. Moreover, methyltransferase-like 3 (METTL3) and serine-threonine kinase protein kinase D2 (PRKD2) was downregulated in skeletal muscle of HFD-fed mouse and in PA-induced C2C12 cells. The online bioinformatic tool SRAMP revealed that there were multiple m6A modification sites in the PRKD2 mRNA sequence. Downregulation of METTL3 enhanced PRKD2 expression by reducing m6A level and promoting mRNA stability in PRKD2 mRNA transcript. Que decreased m6A, METTL3, and phosphorylated insulin receptor substrate 1 (p-IRS1) levels, increased the protein expression of PRKD2, glucose transporter type 4 (GLUT4) and p-AKT, promoted glucose uptake, and reduced oxidative stress in PA-induced C2C12 cells. Moreover, METTL3 overexpression or PRKD2 silence reversed the inhibitory effects of Que on the levels of MDA and p-IRS1 and the promotive effects on glucose uptake, superoxide dismutase (SOD), GSH and GLUT4 and p-AKT levels.

CONCLUSION

Que promoted glucose uptake, repressed oxidative stress and improved IR through METTL3-mediated m6A of PRKD2 mRNA.

Metformin suppresses Oxidative Stress induced by High Glucose via Activation of the Nrf2/HO-1 Signaling Pathway in Type 2 Diabetic Osteoporosis

BACKGROUND

Metformin (MET) is widely used as a first-line hypoglycemic agent for the treatment of type 2 diabetes mellitus (T2DM) and was also confirmed to have a therapeutic effect on type 2 diabetic osteoporosis (T2DOP). However, the potential mechanisms of MET in the treatment of T2DOP are unclear.

OBJECTIVE

To clarify the effect of MET in T2DOP and to explore the potential mechanism of MET in the treatment of T2DOP.

METHODS

In vitro, we used MC3T3-E1 cells to study the effects of MET on osteogenic differentiation and anti-oxidative stress injury in a high glucose (Glucose 25 mM) environment. In vivo, we directly used db/db mice as a T2DOP model and assessed the osteoprotective effects of MET by Micro CT and histological analysis.

RESULTS

In vitro, we found that MET increased ALP activity in MC3T3-E1 cells in a high-glucose environment, promoted the formation of bone mineralized nodules, and upregulated the expression of the osteogenesis-related transcription factors RUNX2, Osterix, and COL1A1-related genes. In addition, MET was able to reduce high glucose-induced reactive oxygen species (ROS) production. In studies on the underlying mechanisms, we found that MET activated the Nrf2/HO-1 signaling pathway and alleviated high-glucose-induced oxidative stress injury. In vivo results showed that MET reduced bone loss and bone microarchitecture destruction in db/db mice.

CONCLUSION

Our results suggest that MET can activate the Nrf2/HO-1 signaling pathway to regulate the inhibition of osteogenic differentiation induced by high glucose thereby protecting T2DOP.

Transcriptomic analysis provides a new insight: Oleuropein reverses high glucose-induced osteogenic inhibition in bone marrow mesenchymal stem cells via Wnt10b activation

Adverse events of diabetes mellitus (DM) include bone damages, such as the increased incidence of osteoporosis and bone fractures, which are known as diabetic osteopathy. The pathogenic mechanism of diabetic osteopathy is complex, and hyperglycemia is a vital cause involved in it. Bone marrow mesenchymal stem cells (BMSCs) exert a significant effect on bone formation. Therefore, in this paper, transcriptomic changes of BMSCs cultured in high glucose (35 mM) for 30 days are mainly investigated. In addition, 794 up-regulated genes and 1,162 down-regulated genes were identified. Then, biological functions of the differentially expressed genes in the high glucose microenvironment were investigated by two kinds of functional analyses. Gene Set Enrichment Analysis was also applied to focus on the significant gene sets and it is found that Wnt10b expression witnessed a remarkable decrease in BMSCs under the high glucose microenvironment. At last, in vitro experiments revealed that oleuropein effectively reversed high glucose-induced osteogenic inhibition via activating Wnt10b in BMSCs.

Lignans as Pharmacological Agents in Disorders Related to Oxidative Stress and Inflammation: Chemical Synthesis Approaches and Biological Activities

Plant lignans exhibit a wide range of biological activities, which makes them the research objects of potential use as therapeutic agents. They provide diverse naturally-occurring pharmacophores and are available for production by chemical synthesis. A large amount of accumulated data indicates that lignans of different structural groups are apt to demonstrate both anti-inflammatory and antioxidant effects, in many cases, simultaneously. In this review, we summarize the comprehensive knowledge about lignan use as a bioactive agent in disorders associated with oxidative stress and inflammation, pharmacological effects in vitro and in vivo, molecular mechanisms underlying these effects, and chemical synthesis approaches. This article provides an up-to-date overview of the current data in this area, available in PubMed, Scopus, and Web of Science databases, screened from 2000 to 2022.

Targeting ferroptosis suppresses osteocyte glucolipotoxicity and alleviates diabetic osteoporosis

Diabetic osteoporosis (DOP) is the leading complication continuously threatening the bone health of patients with diabetes. A key pathogenic factor in DOP is loss of osteocyte viability. However, the mechanism of osteocyte death remains unclear. Here, we identified ferroptosis, which is iron-dependent programmed cell death, as a critical mechanism of osteocyte death in murine models of DOP. The diabetic microenvironment significantly enhanced osteocyte ferroptosis in vitro, as shown by the substantial lipid peroxidation, iron overload, and aberrant activation of the ferroptosis pathway. RNA sequencing showed that heme oxygenase-1 (HO-1) expression was notably upregulated in ferroptotic osteocytes. Further findings revealed that HO-1 was essential for osteocyte ferroptosis in DOP and that its promoter activity was controlled by the interaction between the upstream NRF2 and c-JUN transcription factors. Targeting ferroptosis or HO-1 efficiently rescued osteocyte death in DOP by disrupting the vicious cycle between lipid peroxidation and HO-1 activation, eventually ameliorating trabecular deterioration. Our study provides insight into DOP pathogenesis, and our results provide a mechanism-based strategy for clinical DOP treatment.

A comprehensive review of ethnopharmacology, phytochemistry, pharmacology, and pharmacokinetics of Schisandra chinensis (Turcz.) Baill. and Schisandra sphenanthera Rehd. et Wils

ETHNOPHARMACOLOGICAL RELEVANCE

Schisandra chinensis (called bei-wuweizi in Chinese, S. chinensis) and Schisandra sphenanthera (called nan-wuweizi in Chinese, S. sphenanthera) are two highly similar plants in the Magnoliaceae family. Their dried ripe fruits are commonly used as traditional Chinese medicine in the treatment of coughs, palpitation, spermatorrhea, and insomnia. They also are traditionally used as tonics in Russia, Japan, and Korea.

AIM OF THE REVIEW

S. chinensis and S. sphenanthera are similar in appearance, traditional applications, ingredient compositions, and therapeutic effects. This review, therefore, aims to provide a systematic insight into the botanical background, ethnopharmacology, phytochemistry, pharmacology, pharmacokinetics, quality control, and toxicology of S. chinensis and S. sphenanthera, and to explore and present the similarities and differences between S. chinensis and S. sphenanthera.

MATERIALS AND METHODS

A comprehensive literature search regarding S. chinensis and S. sphenanthera was collected by using electronic databases including PubMed, SciFinder, Science Direct, Web of Science, CNKI, and the online ethnobotanical database.

RESULTS

In the 2020 Edition of Chinese Pharmacopoeia (ChP), there were 100 prescriptions containing S. chinensis, while only 11 contained S. sphenanthera. Totally, 306 and 238 compounds have been isolated and identified from S. chinensis and S. sphenanthera, respectively. Among these compounds, lignans, triterpenoids, essential oils, phenolic acid, flavonoids, phytosterols are the major composition. Through investigation of pharmacological activities, S. chinensis and S. sphenanthera have similar therapeutic effects including hepatoprotection, neuroprotection, cardioprotection, anticancer, antioxidation, anti-inflammation, and hypoglycemic effect. Besides, S. chinensis turns out to have more effects including reproductive regulation and immunomodulatory, antimicrobial, antitussive and antiasthmatic, anti-fatigue, antiarthritic, and bone remodeling effects. Both S. chinensis and S. sphenanthera have inhibitory effects on CYP3A and P-gp, which can mediate metabolism or efflux of substrates, and therefore interact with many drugs.

CONCLUSIONS

S. chinensis and S. sphenanthera have great similarities. Dibenzocyclooctadiene lignans are regarded to contribute to most of the bioactivities. Schisandrin A-C, schisandrol A-B, and schisantherin A, existing in both S. chinensis and S. sphenanthera but differing in the amount, are the main active components, which may contribute to the similarities and differences. Study corresponding to the traditional use is needed to reveal the deep connotation of the use of S. chinensis and S. sphenanthera as traditional Chinese medicine. In addition, a joint study of S. chinensis and S. sphenanthera can better show the difference between them, which can provide a reference for clinical application. It is worth mentioning that the inhibition of S. chinensis and S. sphenanthera on CYP3A and P-gp may lead to undesirable drug-drug interactions.

The SLC27A1 Gene and Its Enriched PPAR Pathway Are Involved in the Regulation of Flavor Compound Hexanal Content in Chinese Native Chickens

The role of hexanal in flavor as an indicator of the degree of oxidation of meat products is undeniable. However, the genes and pathways of hexanal formation have not been characterized in detail. In this study, we performed differential gene expression analysis and weighted gene co-expression network analysis (WGCNA) on groups of Tiannong partridge chickens with different relative hexanal content in order to find the genes involved in the formation of hexanal and the specific pathways of hexanal formation. Then we confirmed the relationship of these candidate genes with hexanal using Jingxing Yellow chicken and Wenchang chicken. In this study, WGCNA revealed a module of co-expressed genes that were highly associated with the volatile organic compound hexanal. We also compared transcriptome gene expression data of samples from chicken groups with high and low relative contents of hexanal and identified a total of 651 differentially expressed genes (DEGs). Among them, 356 genes were up regulated, and 295 genes were downregulated. The different biological functions associated with the DEGs, hub genes and hexanal were identified by functional analysis using the Kyoto Encyclopedia of Genes and Genomes (KEGG) annotations. Among all the hub genes in the significant module identified by WGCNA, more were enriched in the PPAR signaling pathway, the proteasome pathway, etc. Additionally, we found that DEGs and hub genes, including SLC27A1, ACOX3, NR4A1, VEGFA, JUN, EGR1, CACNB1, GADD45A and DUSP1, were co-enriched in the peroxisome proliferator-activated receptor (PPAR) signaling pathway, p53 signaling pathway and mitogen-activated protein kinases (MAPK) signaling pathway, etc. Transcriptome results of the Jingxing Yellow chicken population showed that the SLC27A1 gene was significantly associated with hexanal and enriched in the PPAR pathway. Our study provides a comprehensive insight into the key genes related to hexanal content, and can be further explored by functional and molecular studies.

HO-1 in Bone Biology: Potential Therapeutic Strategies for Osteoporosis

Osteoporosis is a prevalent bone disorder characterized by bone mass reduction and deterioration of bone microarchitecture leading to bone fragility and fracture risk. In recent decades, knowledge regarding the etiological mechanisms emphasizes that inflammation, oxidative stress and senescence of bone cells contribute to the development of osteoporosis. Studies have demonstrated that heme oxygenase 1 (HO-1), an inducible enzyme catalyzing heme degradation, exhibits anti-inflammatory, anti-oxidative stress and anti-apoptosis properties. Emerging evidence has revealed that HO-1 is critical in the maintenance of bone homeostasis, making HO-1 a potential target for osteoporosis treatment. In this Review, we aim to provide an introduction to current knowledge of HO-1 biology and its regulation, focusing specifically on its roles in bone homeostasis and osteoporosis. We also examine the potential of HO-1-based pharmacological therapeutics for osteoporosis and issues faced during clinical translation.

Kansuinine A Ameliorates Atherosclerosis and Human Aortic Endothelial Cell Apoptosis by Inhibiting Reactive Oxygen Species Production and Suppressing IKKβ/IκBα/NF-κB Signaling

Reactive oxygen species (ROS)-induced vascular endothelial cell apoptosis is strongly associated with atherosclerosis progression. Herein, we aimed to examine whether Kansuinine A (KA), extracted from Euphorbia kansui L., prevents atherosclerosis development in a mouse model and inhibits cell apoptosis through oxidative stress reduction. Atherosclerosis development was analyzed in apolipoprotein E-deficient (ApoE^-/-) mice fed a high-fat diet (HFD) using Oil Red O staining and H&E staining. Human aortic endothelial cells (HAECs) were treated with KA, followed by hydrogen peroxide (H₂O₂), to investigate the KA-mediated inhibition of ROS-induced oxidative stress and cell apoptosis. Oil Red O staining and H&E staining showed that atherosclerotic lesion size was significantly smaller in the aortic arch of ApoE^-/- mice in the HFD+KA group than that in the aortic arch of those in the HFD group. Further, KA (0.1-1.0 μM) blocked the H₂O₂-induced death of HAECs and ROS generation. The H₂O₂-mediated upregulation of phosphorylated IKKβ, phosphorylated IκBα, and phosphorylated NF-κB was suppressed by KA. KA also reduced the Bax/Bcl-2 ratio and cleaved caspase-3 expression, preventing H₂O₂-induced vascular endothelial cell apoptosis. Our results indicate that KA may protect against ROS-induced endothelial cell apoptosis and has considerable clinical potential in the prevention of atherosclerosis and cardiovascular diseases.

Non-flavonoid polyphenols in osteoporosis: preclinical evidence

The development of progressive osteopenia and osteoporosis (OP) is due to the imbalance between bone resorption and bone formation, determining a lower bone resistance, major risks of fractures, with consequent pain and functional limitations. Flavonoids, a class of polyphenols, have been extensively studied for their therapeutic activities against bone resorption, but less attention has been given to a whole series of molecules belonging to the polyphenolic compounds. However, these classes have begun to be studied for the treatment of OP. In this systematic review, comprehensive information is provided on non-flavonoid polyphenolic compounds, and we highlight pathways implicated in the action of these molecules that act often epigenetically, and their possible use for OP treatment and prevention.

Association between protoporphyrin IX and sarcopenia: a cross sectional study

Background

According to the European Working Group on Sarcopenia in Older People (EWGSOP), the diagnosis of sarcopenia primarily focused on low muscle strength with the detection of low muscle quality and quantity as confirming index. Many studies had identified mitochondrial dysfunction as one of the multifactorial etiologies of sarcopenia. Yet, no study had investigated the role of biosynthetic pathway intermediate, which was found in mitochondria, in the development of sarcopenia. This study aimed to examine the association between protoporphyrin IX (PPIX) and components of sarcopenia.

Method

The present study enrolled 1172 participants without anemia between 1999 to 2002 from the National Health and Nutrition Examination Survey (NHANES) database. We employed the multivariable-logistic regression model to examine the relationship between PPIX and sarcopenia. Covariate adjustments were designated to each of the three models for further analysis of the relationship.

Results

In the unadjusted model, PPIX was significantly associated with sarcopenia (OR = 3.910, 95% CI = 2.375, 6.439, P value < 0.001). The significance persisted after covariate adjustments as observed in the fully adjusted model (OR = 2.537, 95% CI = 1.419, 4.537, P value = 0.002).

Conclusions

The findings of this study suggested statistically significant association between PPIX and sarcopenia. Our study disclosed the potential of PPIX as a valuable indicator of sarcopenia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02331-6.

Neobavaisoflavone protects osteoblasts from dexamethasone-induced oxidative stress by upregulating the CRNDE-mediated Nrf2/HO-1 signaling pathway

Neobavaisoflavone (NBIF) is a flavonoid, which has a variety of pharmacological activities. However, the mechanism of NBIF in the treatment of osteoporosis still needs further exploration. The differentiation of osteoblast MC-3T3-E1 cells after treatment was observed by Alizarin red staining. Cell counting kit-8 and flow cytometry were used to detect viability, apoptosis, and reactive oxygen species (ROS) levels of treated MC-3T3-E1 cells, respectively. Malondialdehyde (MDA), lactate dehydrogenase (LDH), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were tested by ELISA kits. The expressions of lncRNA MALAT1, MEG3, CRNDE, Runx2, osteocalcin (OCN), osteopontin (OPN), collagen I (col-I), nuclear Nrf2, cytoplasm Nrf2, heme oxygenase-1 (HO-1) and quinone oxidoreductase 1 (NQO1) in treated MC-3T3-E1 cells were examined by Quantitative real-time PCR or Western blot. Dexamethasone (Dex) inhibited the viability of MC-3T3-E1 cells, while the appropriate amount of NBIF had no significantly effect on cell viability. Dex downregulated CRNDE expression, whereas NBIF upregulated CRNDE. Overexpressed CRNDE and NBIF reversed the inhibitory effects of Dex on cell viability, differentiation and levels of SOD, GSH-Px, Runx2, OCN, OPN, col-I, nuclear Nrf2, HO-1 and NQO1 while reversing the promoting effect of Dex on apoptosis and the levels of ROS, MDA, LDH and cytoplasm Nrf2 in MC-3T3-E1 cells, respectively, but shCRNDE further reversed the effects of NBIF in MC-3T3-E1 cells. NBIF protected osteoblasts from Dex-induced oxidative stress by upregulating the CRNDE-mediated Nrf2/HO-1 signaling pathway.

The Effect of Selenium Nanoparticles on the Osteogenic Differentiation of MC3T3-E1 Cells

Reactive oxygen species (ROS) regulate various functions of cells, including cell death, viability, and differentiation, and nanoparticles influence ROS depending on their size and shape. Selenium is known to regulate various physiological functions, such as cell differentiations and anti-inflammatory functions, and plays an important role in the regulation of ROS as an antioxidant. This study aims to investigate the effect of selenium nanoparticles (SeNPs) on the differentiation of osteogenic MC3T3-E1 cells. After fabrication of SeNPs with a size of 25.3 ± 2.6 nm, and confirmation of its oxidase-like activity, SeNPs were added to MC3T3-E1 cells with or without H₂O₂: 5~20 μg/mL SeNPs recovered cells damaged by 200 μM H₂O₂ via the intracellular ROS downregulating role of SeNPs, revealed by the ROS staining assay. The increase in osteogenic maturation with SeNPs was gradually investigated by expression of osteogenic genes at 3 and 7 days, Alkaline phosphatase activity staining at 14 days, and Alizarin red S staining at 28 days. Therefore, the role of SeNPs in regulating ROS and their therapeutic effects on the differentiation of MC3T3-E1 cells were determined, leading to possible applications for bone treatment.

Maqui berry extract prevents cigarette smoke induced oxidative stress in human osteoblasts in vitro

Oxidative stress which can be induced by cigarette smoke (CS) is associated with an altered osteoblast differentiation, and an inhibition of the mineralization process. Therefore, treatments focusing on reducing oxidative stress in osteoblasts could be a potential therapy supporting bone formation. Maqui berry extract (MBE) is the richest natural source of delphinidins with high antioxidant activity. In the present study, we pre-/ co-/ post-incubated MBE in cigarette smoke extract (CSE)-affected human osteoblasts (hOBs), to investigate the effects of MBE as an antioxidant on hOBs. Our results clearly showed that high concentrations of MBE are toxic for hOBs, while physiological concentrations of MBE have no negative effects in vitro. Physiological concentrations of MBE can reduce oxidative stress caused by CSE in hOBs by activating the antioxidative regulator Nrf2 and its regulated antioxidative enzymes. Moreover, the physiological concentration of MBE prevents the detrimental effects of CSE-induced oxidative damage on hOBs by increasing cell viability, differentiation capability and matrix mineralization. Pre-incubation with MBE showed a positive effect on the activation of the cellular antioxidant system in hOBs. Thus, we conclude that MBE at physiological concentrations can effectively protect osteoblasts from oxidative stress-induced damage by activating the cells' antioxidative defense system.

Pharmacodynamic effects and molecular mechanisms of lignans from Schisandra chinensis Turcz. (Baill.), a current review

Fruit of Schisandra chinensis Turcz. (Baill.) (S. chinensis) is a traditional herbal medicine widely used in China, Korea, and many other east Asian countries. At present, S. chinensis commonly forms Chinese medicinal formulae with other herbal medicines to treat liver disease and neurological disease in clinical. Modern researches indicated that lignans were the main active ingredients of S. chinensis with high content and novel dibenzocyclooctadiene skeletal structure, exhibited considerable antioxidant, anti-inflammatory, and neuroprotective properties. Additionally, some of these lignans also showed certain potentials in anti-cancer, anti-fibrosis, and other effects. In the current review, we summarize literature reported lignans from S. chinensis in the past five years, and highlight the molecular mechanisms of lignans in exerting their biological functions. Also, we point out some deficiencies of existing researches and discuss the future direction of lignans study.

Panax ginseng Fruit Has Anti-Inflammatory Effect and Induces Osteogenic Differentiation by Regulating Nrf2/HO-1 Signaling Pathway in In Vitro and In Vivo Models of Periodontitis

Periodontitis is an infectious inflammatory disease of tissues around teeth that destroys connective tissues and is characterized by the loss of periodontal ligaments and alveolar bone. A new treatment strategy is needed owing to the limitations of the current surgical treatment method and the side effects of anti-inflammatory drugs. Therefore, here, we assessed whether Panax ginseng fruit extract (PGFE) is a new therapeutic agent for periodontitis in vitro and in vivo. According to the results, PGFE suppressed pro-inflammatory cytokines such as tumor necrosis factor-α, interleukin (IL)-1β, and IL-6, and pro-inflammatory mediators such as inducible nitric oxide synthase and cyclooxygenase-2 through heme oxygenase-1 expression in human periodontal ligament cells stimulated with Porphyromonas gingivalis lipopolysaccharide (PG-LPS). In addition, the osteogenic induction of human periodontal ligament cells was inhibited by PG-LPS, and protein and mRNA levels of osteogenic markers such as alkaline phosphatase, collagen type 1 (COL1), osteopontin (OPN), and runt-related transcription factor 2 (RUNX2) were increased. The efficacy of PGFE for inhibiting periodontitis in vitro was demonstrated in a representative in vitro model of periodontitis induced by ligature and PG-LPS. Subsequently, hematoxylin and eosin staining and micro-computed tomography of the euthanized experimental animal model confirmed suppressed periodontal inflammation, which is an important strategy for treating periodontitis and for recovering the resulting alveolar bone loss. Therefore, PGFE is a potential, novel therapeutic agent for periodontal diseases.

Inhibitory Effectiveness of Gomisin A, a Dibenzocyclooctadiene Lignan Isolated from Schizandra chinensis, on the Amplitude and Gating of Voltage-Gated Na+ Current

Gomisin A (Gom A), a lignan isolated from Schisandra chinensis, has been reported produce numerous biological activities. However, its action on the ionic mechanisms remains largely unanswered. The present experiments were undertaken to investigate the possible perturbations of Gom A or other related compounds on different types of membrane ionic currents in electrically excitable cells (i.e., pituitary GH₃ and pancreatic INS-1 cells). The exposure to Gom A led to the differential inhibition of peak and end-pulse components of voltage-gated Na⁺ current (I_Na) in GH₃ cells with effective IC₅₀ of 6.2 and 0.73 μM, respectively. The steady-state inactivation curve of I_Na in the presence of Gom A was shifted towards a more hyperpolarized potential. However, neither changes in the overall current-voltage relationship nor those for the gating charge of the current were demonstrated. The application of neither morin (10 μM) nor hesperidin (10 μM) perturbed the strength of I_Na, while sesamine could suppress it. However, in the continued presence of Gom A, the addition of sesamine failed to suppress I_Na further. Gom A also effectively suppressed the strength of persistent I_Na activated by long ramp voltage command, and further application of tefluthrin effectively attenuated Gom A-mediated inhibition of the current. The presence of Gom A mildly inhibited erg-mediated K⁺ current, while a lack of change in the amplitude of hyperpolarization-activated cation current was observed in its presence. Under cell-attached current recordings, the exposure to Gom A resulted in the decreased firing of spontaneous action currents with a minimal change in AC amplitude. In pancreatic INS-1 cells, the presence of Gom A was also noticed to inhibit peak and end-pulse components of I_Na differentially with the IC₅₀ of 5.9 and 0.84 μM, respectively. Taken together, the emerging results presented herein provide the evidence that Gom A can differentially inhibit peak and sustained I_Na in endocrine cells (e.g., GH₃ and INS-1 cells).

Schisandrin B Inhibits Osteoclastogenesis and Protects Against Ovariectomy-Induced Bone Loss

Osteoporosis is a systemic skeletal disease which is highly prevalent worldwide and considered to be associated with excessive bone resorption mediated by osteoclast. Osteoclast differentiation is featured by the activation of inflammation-related pathways and the generation of reactive oxygen species. Schisandrin B is a bioactive compound with strong antiinflammation and antioxidative properties, we thus speculated that Schisandrin B might serve as a potential candidate for osteoporosis. In the present study, we found that the formation and` function of osteoclasts were dramatically suppressed by Schisandrin B. And consistent with the in vitro results, treatment with Schisandrin B attenuated ovariectomy-induced bone loss in mice. Moreover, Schisandrin B notably inhibited the activation of mitogen activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) pathways and scavenged ROS by activating nuclear factor E2 p45-related factor 2 (Nrf2) signaling. In conclusion, our study indicates that Schisandrin B is an effective approach to treat osteoporosis and other osteoclast-related diseases.

Metformin promotes cell proliferation and osteogenesis under high glucose condition by regulating the ROS‑AKT‑mTOR axis

Metformin, a cost-effective and safe orally administered antidiabetic drug used by millions of patients, has exhibited great interest for its potential osteogenic-promoting properties in different types of cells, including mesenchymal stem cells (MSCs). Diabetic osteopathy is a common comorbidity of diabetes mellitus; however, the underlying molecular mechanisms of metformin on the physiological processes of MSCs, under high glucose condition, remain unknown. To determine the effects of metformin on the regulatory roles of proliferation and differentiation in MSCs, under high glucose conditions, osteogenesis after metformin treatment was detected with Alizarin Red S and ALP staining. The results demonstrated that high glucose levels significantly inhibited cell proliferation and osteogenic differentiation under high glucose conditions. Notably, addition of metformin reversed the inhibitory effects induced by high glucose levels on cell proliferation and osteogenesis. Furthermore, high glucose levels significantly decreased mitochondrial membrane potential (MMP), whereas treatment with metformin helped maintain MMP. Further analysis of mitochondrial function revealed that metformin significantly promoted ATP synthesis, mitochondrial DNA mass and mitochondrial transcriptional activity, which were inhibited by high glucose culture. Furthermore, metformin significantly scavenged reactive oxygen species (ROS) induced by high glucose levels, and regulated the ROS-AKT-mTOR axis inhibited by high glucose levels, suggesting the protective effects of metformin against high glucose levels via regulation of the ROS-AKT-mTOR axis. Taken together, the results of the present study demonstrated the protective role of metformin on the physiological processes of MSCs, under high glucose condition and highlighted the potential molecular mechanism underlying the effect of metformin in promoting cell proliferation and osteogenesis under high glucose condition.