Salidroside protects endothelial cells against LPS-induced inflammatory injury by inhibiting NLRP3 and enhancing autophagy

Mechanistic insights into targeting caspase-3 activation and alveolar macrophage pyroptosis by Ephedra and bitter almond compounds for treating pediatric pneumonia via network pharmacology and bioinformatics

This study investigates the molecular mechanism of Ma Huang-Ku Xing Ren, a traditional Chinese medicine formula, in treating pediatric pneumonia. The focus is on the regulation of caspase-3 activation and reduction of alveolar macrophage necrosis through network pharmacology and bioinformatics analyses of Ephedra and bitter almond components. Active compounds and targets from ephedrine and bitter almond were obtained using TCMSP, TCMID, and GeneCards databases, identifying pediatric pneumonia-related genes. A protein-protein interaction (PPI) network was constructed, and core targets were screened. GO and KEGG pathway enrichment analyses identified relevant genes and pathways. An acute pneumonia mouse model was created using the lipopolysaccharide (LPS) inhalation method, with caspase-3 overexpression induced by a lentivirus. The mice were treated with Ephedra and bitter almond through gastric lavage. Lung tissue damage, inflammatory markers (IL-18 and IL-1β), and cell death-related gene activation were assessed through H&E staining, ELISA, western blot, flow cytometry, and immunofluorescence. The study identified 128 active compounds and 121 gene targets from Ephedra and bitter almond. The PPI network revealed 13 core proteins, and pathway analysis indicated involvement in inflammation, apoptosis, and cell necrosis, particularly the caspase-3 pathway. In vivo results showed that Ephedra and bitter almond treatment significantly mitigated LPS-induced lung injury in mice, reducing lung injury scores and inflammatory marker levels. It also decreased caspase-3 activity and cell death in alveolar macrophages. In conclusion, the active ingredients of Ma Huang-Ku Xing Ren, particularly targeting caspase-3, may effectively treat pediatric pneumonia by reducing apoptosis in alveolar macrophages, as demonstrated by both network pharmacology, bioinformatics analyses, and experimental data.

Application and value of hydrogen sulfide modulated autophagy in sepsis

Sepsis is is anabnormalhost immune responsecausedbyinfection. Antibiotics, anti-viral drugs, and vasoactive drugs have always been used in the traditional treatment of sepsis, but there are no specific and effective drugs in clinical practice. Autophagy is a highly conservative process in biological evolution, and plays an important role in maintaining intracellular homeostasis and cellular self-renewal. Autophagy can remove and degrade misfolding proteins and damaged organelles in cells, providing materials for cell repair and self-renewal. Hydrogen sulfide (H2S) is a colorless gas that smells likerotteneggs. It is the third endogenous gas signal molecule discovered after nitric oxide and carbon monoxide and has become a research hotspot in recent years. H2S has a variety of biological functions and plays an important role in various physiological and pathological processes. Thereisgrowingevidencethat H2S can regulate autophagy. The intervention of autophagy is a promising therapeutic strategy to improve sepsis organ damage. This article reviews the organ protection of autophagy in sepsis and the role of H2S in regulating autophagy in sepsis, revealing that H2S intervention with autophagy may be a a worthy target in sepsis treatment.

Salidroside alleviates oxidative stress in dry eye disease by activating autophagy through AMPK-Sirt1 pathway

Dry eye disease (DED) is a multifactorial disease, and oxidative stress plays a crucial role in its pathogenesis. Recently, multiple studies have shown that upregulation of autophagy can protect the cornea from oxidative stress damage. The present study investigated the therapeutic effects of salidroside, the main component of Rhodiola crenulata, in both in vivo and in vitro dry eye models. The results showed that topical eye drop treatment with salidroside restored corneal epithelium damage, increased tear secretion, and reduced cornea inflammation in the DED mice. Salidroside activated autophagy through AMP-activated protein kinase (AMPK)-sirtuin-1 (Sirt1) signaling pathway, which promoted the nuclear translocation of nuclear factor erythroid-2-related factor 2 (Nrf2) and increased the expression of downstream antioxidant factors heme oxygenase-1 (HO-1) and NAD(P)H quinone dehydrogenase 1 (NQO1). This process restored antioxidant enzyme activity, reduced reactive oxygen species (ROS) accumulation, and alleviated oxidative stress. The application of autophagy inhibitor chloroquine and AMPK inhibitor Compound C reversed the therapeutic efficacy of salidroside, validating the above findings. In conclusion, our data suggest that salidroside is a promising candidate for DED treatment.

Salidroside attenuates lipopolysaccharide-induced neuroinflammation and cognitive impairment in septic encephalopathy mice

Salidroside (SAL) is a natural bioactive compound with anti-oxidative, anti-inflammatory, and neuroprotective properties. In the present study, we generate an experimental design to investigate SAL-mediated protective effect and underlying mechanism on lipopolysaccharide (LPS)-induced neuroinflammation and cognitive impairment in the septic encephalopathy mice model (SEMM). In SEMM, Open-Field Test (OFT) and Novel Object Recognition Test evaluated LPS-induced cognitive impairment, behavioural phenotypes, and memory impairment (NOR). Cytokines and protein expression were assessed using ELISA assay, RT-qPCR, and Western blotting. Our results showed cognitive dysfunction could be reversed when treated with SAL in SEMM. SAL treatment significantly reduced apoptotic TUNEL-positive cells and related gene expression (BAX and BCL-2) and considerably improved neuronal damage in SEMM. In addition, it markedly reduced the production of inflammatory cytokines (TNF-α, IL-1β, and IL-6) and Iba-1-positive cells responsible for microglial activation in mice hippocampus (P < 0.05). The effects of SAL on ROS and oxidative stress markedly reduced malondialdehyde (MDA) content and increased superoxide dismutase (SOD) and catalase (CAT) in the hippocampal tissues of mice. Besides, SAL treatment enhanced LPS-induced autophagy in mice's hippocampus and increased autophagy-related protein expression (Beclin-1 and P62). In addition, the NLRP3 inflammasome pathway and its related proteins (NLRP3, ASC, and cleaved caspase-1) were suppressed by SAL treatment. However, SAL activated the SIRT1/Nrf2 pathway and exerts protection by enhanced expression of the proteins (SIRT1 and Nrf2) and downstream genes (HO-1 and NQO1). Our finding demonstrated that SAL employed neuroprotective effects in SEMM by promoting autophagy via activation of the SIRT1 pathway.

Spermidine-Eugenol Supplement Preserved Inflammation-Challenged Intestinal Cells by Stimulating Autophagy

Increases in non-communicable and auto-immune diseases, with a shared etiology of defective autophagy and chronic inflammation, have motivated research both on natural products in drug discovery fields and on the interrelationship between autophagy and inflammation. Within this framework, the tolerability and protective effects of a wheat-germ spermidine (SPD) and clove eugenol (EUG) combination supplement (SUPPL) were investigated on inflammation status (after the administration of lipopolysaccharide (LPS)) and on autophagy using human Caco-2 and NCM460 cell lines. In comparison to the LPS treatment alone, the SUPPL + LPS significantly attenuated ROS levels and midkine expression in monocultures, as well as occludin expression and mucus production in reconstituted intestinal equivalents. Over a timeline of 2-4 h, the SUPPL and SUPPL + LPS treatments stimulated autophagy LC3-11 steady state expression and turnover, as well as P62 turnover. After completely blocking autophagy with dorsomorphin, inflammatory midkine was significantly reduced in the SUPPL + LPS treatment in a non-autophagy-dependent manner. After a 24 h timeline, preliminary results showed that mitophagy receptor BNIP3L expression was significantly downregulated in the SUPPL + LPS treatment compared to the LPS alone, whereas conventional autophagy protein expression was significantly higher. The SUPPL shows promise in reducing inflammation and increasing autophagy to improve intestinal health.

TPPU inhibits inflammation-induced excessive autophagy to restore the osteogenic differentiation potential of stem cells and improves alveolar ridge preservation

Inflammation-induced autophagy is a double-edged sword. Dysfunction of autophagy impairs the differentiation capacity of mesenchymal stem cells and enhances inflammation-induced bone loss. Tooth extraction with periodontal and/or endodontic lesions exacerbates horizontal and vertical resorption of alveolar bone during the healing period. Alveolar socket preservation (ASP) procedure following tooth extraction has important clinical implications for future prosthodontic treatments. Studies have shown that epoxyeicosatrienoic acids (EETs) have significant anti-inflammatory effects and participate in autophagy. However, whether EETs can minimize alveolar bone resorption and contribute to ASP by regulating autophagy levels under inflammatory conditions remain elusive. Here, we figured out that LPS-induced inflammatory conditions increased the inflammatory cytokine and inhibited osteogenic differentiation of human dental pulp stem cells (hDPSCs), and led to excessive autophagy of hDPSCs. Moreover, we identified that increased EETs levels using TPPU, a soluble epoxide hydrolase inhibitor, reversed these negative outcomes. We further demonstrated the potential of TPPU to promote early healing of extraction sockets and ASP, and speculated that it was related to autophagy. Taken together, these results suggest that targeting inhibition of soluble epoxide hydrolase using TPPU plays a protective role in the differentiation and autophagy of mesenchymal stem cells and provides potential feasibility for applying TPPU for ASP, especially under inflammatory conditions.

Traditional Chinese medicine for treatment of sepsis and related multi-organ injury

Sepsis is a common but critical illness in patients admitted to the intensive care unit and is associated with high mortality. Although there are many treatments for sepsis, specific and effective therapies are still lacking. For over 2,000 years, traditional Chinese medicine (TCM) has played a vital role in the treatment of infectious diseases in Eastern countries. Both anecdotal and scientific evidence show that diverse TCM preparations alleviate organ dysfunction caused by sepsis by inhibiting the inflammatory response, reducing oxidative stress, boosting immunity, and maintaining cellular homeostasis. This review reports on the efficacy and mechanism of action of various TCM compounds, herbal monomer extracts, and acupuncture, on the treatment of sepsis and related multi-organ injury. We hope that this information would be helpful to better understand the theoretical basis and empirical support for TCM in the treatment of sepsis.

Salidroside attenuates cerebral ischemia/reperfusion injury by regulating TSC2-induced autophagy

Salidroside (SAL), an antioxidant derived from Rhodiola rosea, exerts neuroprotective effects in cerebral ischemia/reperfusion (I/R) injury; however, the mechanisms have not been fully elucidated. The present study established a rat model of middle cerebral artery occlusion/reperfusion (MCAO/R) and a cellular model of oxygen-glucose deprivation/reoxygenation (OGD/R) to explore the roles and mechanisms of SAL in cerebral I/R injury. The rat model of MCAO/R was established and rats were treated with different doses of SAL. The Zea-Longa scoring system and 2,3,5-triphenyltetrazolium chloride (TTC) staining showed that SAL reduced neurological deficit scores and cerebral infarct volumes in MCAO/R rats. The results of Morris water maze (MWM) test showed that SAL reduced memory impairment in MCAO/R rats. In addition, SAL significantly reduced oxidative stress and suppressed inflammatory response. Next, the OGD/R model was established with PC12 cells and treated with SAL. The results of flow cytometry and 3-(4, 5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assays showed that SAL reduced apoptosis, enhanced cell viability and protected neuronal cells from damage by decreasing lactate dehydrogenase (LDH) activity. SAL increased the expression of TSC complex subunit 2 (TSC2), and activated the 5'-AMP-activated protein kinase (AMPK) and inhibited the mammalian target of rapamycin (mTOR) signaling pathways. It was verified that SAL alleviated cerebral I/R injury by regulating the AMPK/TSC2/mTOR pathway to induce autophagy. In conclusion, SAL reduces the inflammatory response and oxidative stress in a concentration-dependent manner, and protects against cerebral I/R injury by modulating TSC2-induced autophagy. These findings suggest SAL may prove to be a potential therapeutic agent for ischemic stroke.

Salidroside intensifies mitochondrial function of CoCl2-damaged HT22 cells by stimulating PI3K-AKT-MAPK signaling pathway

BACKGROUND

Salidroside (Sal), an active component from Rhodiola crenulata, has been confirmed to exert neuroprotective effects against hypoxia. However, its molecular mechanisms of intensifying mitochondrial function still largely unknown. In the present study, we aimed to explore the mechanisms by which Sal heightened mitochondrial function in CoCl₂-induced HT22 hypoxic injury.

METHODS

The hypoxic condition of HT22 cells was performed by CoCl₂ stimulus. We then investigated the effects of Sal on the viability of hypoxic HT22 cells by cell counting kit-8. The contents of lactate dehydrogenase (LDH) release in cultured supernatant were detected by using commercial biochemical kit. Superoxide free radical scavenging activity, total antioxidant capacity assay kit with ferric reducing ability of plasma and 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) methods were employed to detect the free radical scavenging ability and antioxidant capacity of Sal. Meanwhile, intracellular reactive oxygen species (ROS), Ca2+ and mitochondrial membrane potential (MMP) were determined by corresponding specific labeled probes. Mitochondrial morphology was tested by Mito-tracker green with confocal microscopy. Hoechst 33342 and Annexin V-FITC/propidium iodide staining were also employed to evaluate the effect of Sal on cell apoptosis. Oxygen consumption rate (OCR), real-time ATP production and proton efflux rate were measured using a Seahorse analyzer. Additionally, the potential interactions of Sal with PI3K-AKT signaling pathway-related proteins were predicted and tested by molecular docking, molecular dynamics simulation (MDS) and localized surface plasmon resonance (LSPR) techniques, respectively. Furthermore, the protein levels of p-PI3K, PI3K, p-AKT, AKT, p-JNK, JNK, p-p38 and p38 were estimated by western blot analysis.

RESULTS

Sal alleviated CoCl2-induced hypoxic injury in HT22 cells as evidenced by increased cell viability and decreased LDH release. In vitro antioxidant test confirmed that Sal had marvelous antioxidant abilities. The protected mitochondrial function by Sal treatment was illustrated by the decrease of ROS, Ca2+, mitochondrial fragment and the increase of MMP. In addition, Sal ameliorated the apoptosis of HT22 cells by decreasing Hoechst 33342 positive cells and the rate of apoptotic cells. Enhancement of energy metabolism in HT22 by Sal was demonstrated by increased OCR, real-time ATP generation and proton efflux rate. The molecular docking confirmed the potential binding of Sal to PI3K, AKT and CaMK II proteins with calculated binding energy of -1.32, -4.21 and -4.38 kcal/mol, respectively. The MDS test revealed the average hydrogen bond of complex Sal-PI3K and Sal-AKT were 0.79 and 4.46, respectively. The results of LSPR verified the potential binding of Sal to proteins PI3K, AKT and HIF-1α with affinity values of 5.20 × 10 - 3, 2.83 × 10 - 3 and 3.97 × 10 - 3 KD, respectively. Western blot analysis further argued that Sal consolidated the levels of p-PI3K and p-AKT. Meanwhile, Sal could downregulate the proteins expression of p-JNK and p-p38.

CONCLUSION

Collectively, our findings suggested that Sal can intensify mitochondrial function of CoCl2-simulated hypoxia injury in HT22 cells by stimulating PI3K-AKT-MAPK signaling pathway. Sal is a potential agent for mitochondrial protection against hypoxia with the underlying molecular mechanisms of energy metabolism being further elucidated.

Triterpenoid saponins of Ilex pubescens against TNF-α induced inflammation and apoptosis in human umbilical vein endothelial cells via autophagy pathway

OBJECTIVES

Triterpenoid saponins of Ilex pubescens (IPTS), the main active components of Ilex pubescens, has a therapeutic effect on atherosclerosis (AS). The ingredients in IPTS that could be intracellularly transported by human umbilical vein endothelial cells (HUVECs) may play an essential role in AS. This study attempted to explore its mechanism from the perspectives of HUVECs' inflammation, apoptosis, and autophagy.

METHODS

By using a tumour necrosis factor-α (TNF-α)-induced HUVECs injury model, cell viability and the expression of intercellular adhesion molecule 1 (ICAM1), matrix metalloproteinase 9 (MMP9), cleave-caspase-3 and cleave-caspase-9, in combination with the results of flow cytometry, JC-1 and Hoechst 33258 staining were investigated to evaluate the anti-inflammatory and anti-apoptotic impact effects of IPTS on HUVECs. Afterwards, the expression of microtubule-associated proteins light chain 3II (LC3II) and sequestosome 1 (p62) was determined to test the effect of IPTS on autophagy. Finally, by adding an autophagy inhibitor 3-methyladenine (3-MA), we investigated whether IPTS exerts anti-inflammatory and anti-apoptotic effects through the autophagy pathway.

KEY FINDINGS

We firstly demonstrated that pretreatment with IPTS could increase the cell viability, maintain the cell morphology and reduce TNF-α-induced inflammation and apoptosis of HUVECs. Moreover, IPTS pretreatment was proved to raise the expression of LC3II /LC3I while decreasing the expression of p62, which indicated that IPTS could activate HUVECs' autophagy. IPTS has been shown for the first time to exert anti-inflammatory and anti-apoptotic effects through autophagy and thereby resisting TNF-α-induced inflammatory injury of HUVECs.

CONCLUSIONS

This study preliminarily confirmed that IPTS ameliorated HUVECs' inflammation and apoptosis by increasing autophagy.

Lipopolysaccharide affects energy metabolism and elevates nicotinamide N-methyltransferase level in human aortic endothelial cells (HAEC)

This study aimed to investigate the putative role of nicotinamide N-methyltransferase in the metabolic response of human aortic endothelial cells. This enzyme catalyses S-adenosylmethionine-mediated methylation of nicotinamide to methylnicotinamide. This reaction is accompanied by the reduction of the intracellular nicotinamide and S-adenosylmethionine content. This may affect NAD⁺ synthesis and various processes of methylation, including epigenetic modifications of chromatin. Particularly high activity of nicotinamide N-methyltransferase is detected in liver, many neoplasms as well as in various cells in stressful conditions. The elevated nicotinamide N-methyltransferase content was also found in endothelial cells treated with statins. Although the exogenous methylnicotinamide has been postulated to induce a vasodilatory response, the specific metabolic role of nicotinamide N-methyltransferase in vascular endothelium is still unclear. Treatment of endothelial cells with bacterial lipopolysaccharide evokes several metabolic and functional consequences which built a multifaceted physiological response of endothelium to bacterial infection. Among the spectrum of biochemical changes substantially elevated protein level of nicotinamide N-methyltransferase was particularly intriguing. Here it has been shown that silencing of the nicotinamide N-methyltransferase gene influences several changes which are observed in cells treated with lipopolysaccharide. They include altered energy metabolism and rearrangement of the mitochondrial network. A complete explanation of the mechanisms behind the protective consequences of the nicotinamide N-methyltransferase deficiency in cells treated with lipopolysaccharide needs further investigation.

Modulation of Disordered Bile Acid Homeostasis and Hepatic Tight Junctions Using Salidroside against Hepatocyte Apoptosis in Furan-Induced Mice

Furan, a processing-induced food contaminant, has attracted great attention due to its hepatotoxicity. To further investigate the underlying mechanism of salidroside (SAL) alleviating furan-induced liver damage, we divided Balb/c mice into the control group, the furan (8 mg/kg/day) group, and three groups of three different doses of SAL (10/20/40 mg/kg/day) in the current research. The shifted serum profile was observed through untargeted metabonomics, to which the bile acid metabolism was related, and the alleviating effect of SAL against furan-induced apoptosis was caused by the metabolism. Target bile acid quantification for the liver and serum showed that SAL positively regulated the homeostasis of bile acids disturbed by furan. Meanwhile, SAL significantly upregulated the synthesis genes of bile acids (Cyp7a1, Cyp7b1, Cyp8b1, and Cyp27a1) and the uptake transport genes (Ntcp and Oatps) and downregulated the efflux transport genes (Bsep, Ost-α, Ost-β, Mrp2, and Mrp4). Transmission electron microscopy of the bile canaliculi and tight junctions and the levels of tight junction marker proteins (ZO-1, occludin, and claudin-1) confirmed that the disruption of the hepatic tight junction was inhibited by SAL. The connection between the apoptosis- and tight junction-related proteins was observed through the construction of a protein-protein interaction network. SAL suppressed the furan-induced hepatocyte apoptosis evidenced by the detection of TUNEL and Bax, Bcl-2, and caspase-3 levels. Taken together, SAL alleviated furan-induced hepatocyte apoptosis via altering the disordered homeostasis of bile acids and hepatic tight junctions.

Salidroside Ameliorates Ultraviolet-Induced Keratinocyte Injury by Inducing SIRT1-Dependent Autophagy

Introduction

Methods

Results

Discussion

Wheat Germ Spermidine and Clove Eugenol in Combination Stimulate Autophagy In Vitro Showing Potential in Supporting the Immune System against Viral Infections

Impaired autophagy, responsible for increased inflammation, constitutes a risk factor for the more severe COVID-19 outcomes. Spermidine (SPD) is a known autophagy modulator and supplementation for COVID-19 risk groups (including the elderly) is recommended. However, information on the modulatory effects of eugenol (EUG) is scarce. Therefore, the effects of SPD and EUG, both singularly and in combination, on autophagy were investigated using different cell lines (HBEpiC, SHSY5Y, HUVEC, Caco-2, L929 and U937). SPD (0.3 mM), EUG (0.2 mM) and 0.3 mM SPD + 0.2 mM EUG, significantly increased autophagy using the hallmark measure of LC3-II protein accumulation in the cell lines without cytotoxic effects. Using Caco-2 cells as a model, several crucial autophagy proteins were upregulated at all stages of autophagic flux in response to the treatments. This effect was verified by the activation/differentiation and migration of U937 monocytes in a three-dimensional reconstituted intestinal model (Caco-2, L929 and U937 cells). Comparable benefits of SPD, EUG and SPD + EUG in inducing autophagy were shown by the protection of Caco-2 and L929 cells against lipopolysaccharide-induced inflammation. SPD + EUG is an innovative dual therapy capable of stimulating autophagy and reducing inflammation in vitro and could show promise for COVID-19 risk groups.

Salidroside Exerts Beneficial Effect on Testicular Ischemia-Reperfusion Injury in Rats

Testicular torsion-detorsion results in testicular ischemia-reperfusion injury, which is associated with overgeneration of reactive oxygen species. Salidroside, a major bioactive ingredient extracted from Rhodiola rosea, has strong antioxidant activity. The purpose of this study was to examine the effect of salidroside on testicular ischemia-reperfusion injury. Sixty rats were randomly separated into 3 experimental groups: group A = sham-operated control; group B = testicular ischemia-reperfusion; and group C = testicular ischemia-reperfusion treated with salidroside. The rats in the sham-operated control group received all surgical procedures except testicular torsion-detorsion. The testicular ischemia-reperfusion group underwent 2 hours of left testicular torsion followed by detorsion. The rats in the salidroside-treated group received the same surgical procedure as in testicular ischemia-reperfusion group, but salidroside was injected intraperitoneally at reperfusion. Testicular malondialdehyde content (a reliable index of reactive oxygen species) and protein expression of superoxide dismutase and catalase which are primary antioxidant enzymes in testes were measured at 4 hours after reperfusion. Testicular spermatogenesis was evaluated at 3 months after reperfusion. The malondialdehyde content increased significantly, while superoxide dismutase and catalase protein expression and testicular spermatogenesis reduced significantly in ipsilateral testes of testicular ischemia-reperfusion group, as compared with sham-operated control group. Therapy with salidroside significantly reduced malondialdehyde content and significantly enhanced superoxide dismutase and catalase protein expression and spermatogenesis in ipsilateral testes, as compared with testicular ischemia-reperfusion group. The present findings indicate that treatment with salidroside ameliorates testicular ischemia-reperfusion injury by reducing reactive oxygen species level by upregulating superoxide dismutase and catalase protein expression.

Salidroside Protects Acute Kidney Injury in Septic Rats by Inhibiting Inflammation and Apoptosis

Purpose

To clarify the protective effect and mechanism of salidroside (SLDS) on acute kidney injury (AKI) in septic rats.

Methods

We pretreated rats with different doses of SLDS and analyzed the impact of SLDS on the survival of septic rats. We evaluated the levels of inflammatory factors in rats, the expression of NF-ƙB p65 in the kidney, and the apoptosis of kidney tubular epithelial cells (KTECs).

Results

SLDS significantly decreased the mortality of septic rats, and it reduced the levels of TNF-α, IL-1β, and IL-17A in plasma and kidneys and decreased the levels of serum creatinine, plasma renal injury molecule-1 and plasma neutrophil gelatin-associated lipocalin. Moreover, SLDS could significantly decrease the expression of NF-ƙB p65 in kidney tissues and the apoptotic number of KETCs, while reducing the mRNA levels of Caspase-3 and Bax mRNA, and increasing the level of Bcl-2 mRNA.

Conclusion

SLDS pretreatment protects against AKI in septic rats by inhibiting the inflammation of kidney and the apoptosis of KTECs.

Improvement of polydopamine-loaded salidroside on osseointegration of titanium implants

Background

Microarc oxidation (MAO) on the surface of medical pure titanium can improve its histocompatibility, and loading drugs on the surface can resist excessive intimal hyperplasia.

Methods

In this study, salidroside (SAL) was loaded on the surface of porous titanium (Ti) with polydopamine (PDA) carrier. The effects of SAL on the osteogenesis and angiogenesis of Ti implants were studied by phalloidin staining, alizarin red staining, ALP staining, wound-healing assay, cell transwell assay, matrigel tube formation, and osteogenic and angiogenic genes and proteins expression detected by PCR and western blot in vitro. The bone defect model experiments in rats was established in vivo including X-ray, micro CT, hematoxylin and eosin staining (HE), immunohistochemistry (IHC), Goldner's trichrome analysis, Safranin O-fast green staining and determination of contents of TNF-α and IL-6 in serum.

Results

EDS and EDS mapping showed that SAL could be loaded on the surface of the MAO coating by PDA. A drug release experiment showed that SAL loaded on the Ti coating could release slowly and stably without sudden release risk. In vitro cell experiments showed that the SAL coating could promote the proliferation, morphology, calcification and alkaline phosphate activity of MC3T3-E1 cells. At the same time, it promoted the migration and tube formation of HUVEC cells. The SAL coating promoted osteogenesis and angiogenesis by promoting the expression of genes and proteins related to. In vivo experiments, HE and IHC showed that SAL significantly promoted the expression of COL-1 and CD31. Goldner's trichrome and Safranin O-fast green staining showed that SAL coating could increase the new bone tissue around the implantation site. The SAL coating had anti-inflammatory activity by reducing the levels of TNF-α and IL-6 in vivo.

Conclusion

Therefore, SAL could improve osteogenesis and angiogenesis in conjunction with the Ti-PDA coating.