Salidroside Group Research Articles

Salidroside Ameliorates Lung Injury Induced by PM2.5 by Regulating SIRT1-PGC-1α in Mice

ObjectiveThis study aimed to clarify the intervention effect of salidroside (SAL) on lung injury caused by PM2.5 in mice and illuminate the function of SIRT1-PGC-1ɑ axis. MethodsSpecific pathogen-free (SPF) grade male C57BL/6 mice were randomly assigned to the following groups: control group, SAL group, PM2.5 group, SAL+PM2.5 group. On the first day, SAL was given by gavage, and on the second day, PM2.5 suspension was given by intratracheal instillation. The whole experiment consist of a total of 10 cycles, lasting 20 days. At the end of treatment, blood samples and lung tissues were collected and analyzed. Observation of pathological changes in lung tissue using inverted microscopy and transmission electron microscopy. The expression of inflammatory, antioxidants, apoptosis, and SIRT1-PGC-1ɑ proteins were detected by Western blotting. ResultsExposure to PM2.5 leads to obvious morphological and pathologica changes in the lung of mice. PM2.5 caused a decline in levels of antioxidant-related enzymes and protein expressions of HO-1, Nrf2, SOD2, SIRT1 and PGC-1ɑ, and an increase in the protein expressions of IL-6, IL-1β, Bax, caspase-9 and cleaved caspase-3. However, SAL reversed the aforementioned changes caused by PM2.5 by activating the SIRT1-PGC-1α pathway. ConclusionSAL can activate SIRT1-PGC-1ɑ to ameliorate PM2.5-induced lung injury.

Protective effect of salidroside on renal damage in diabetic nephropathy mice by regulating RAGE/JAK1/STAT signaling pathway

This study aims to investigate the protective effect of salidroside(SAL) on renal damage in diabetic nephropathy(DN) mice based on the receptor for advanced glycation end products/janus activated kinase 1/signal transduction and activator of transcription 3(RAGE/JAK1/STAT3) signaling pathway. The mouse DN model was established by high-fat/high-sucrose diets combined with intraperitoneal injection of streptozocin(STZ). Mice were randomly divided into normal group, model group, low-dose SAL group(20 mg·kg~(-1)), high-dose SAL group(100 mg·kg~(-1)), and metformin group(140 mg·kg~(-1)), with 12 mice in each group. After establishing the DN model, mice were given drugs or solvent intragastrically, once a day for consecutive 10 weeks. Body weight, daily water intake, and fasting blood glucose(FBG) were measured every two weeks. After the last dose, the glucose tolerance test was performed, and the samples of 24-hour urine, serum, and kidney tissue were collected. The levels of 24 hours urinary total protein(24 h-UTP), serum creatinine(Scr), blood urea nitrogen(BUN), triglyceride(TG), total cholesterol(TC), low density lipoprotein cholesterol(LDL-C), and high density lipoprotein cholesterol(HDL-C) were detected by biochemical tests. Periodic acid-schiff(PAS) staining was used to observe the pathological changes in the kidney tissue. The protein expressions of α-smooth muscle actin(α-SMA), vimentin, and advanced glycation end products(AGEs) in kidneys were detected by immunohistochemical staining. The activities of superoxide dismutase(SOD), catalase(CAT), glutathione peroxidase(GSH-PX), and the level of malondialdehyde(MDA) in kidneys were detected by using a corresponding detection kit. Enzyme-linked immunosorbent assay(ELISA) was used to detect the levels of AGEs, carboxymethyllysine(CML), and carboxyethyllysine(CEL) in serum. The protein expressions of RAGE and the phosphorylation level of JAK1 and STAT3 in kidneys were detected by Western blot. Compared with the normal group, the levels of FBG, the area under the curve of glucose(AUCG), water intake, kidney index, 24 h-UTP, tubular injury score, extracellular matrix deposition ratio of the renal glomerulus, the serum levels of Scr, BUN, TG, LDL-C, AGEs, CEL, and CML, the level of MDA, the protein expressions of α-SMA, vimentin, AGEs, and RAGE, and the phosphorylation level of JAK1 and STAT3 in kidney tissue were increased significantly(P<0.01), while the level of HDL-C in serum and the activity of SOD, CAT, and GSH-PX in kidney tissue were decreased significantly(P<0.01). Compared with the model group, the above indexes of the high-dose SAL group were reversed significantly(P<0.05 or P<0.01). In conclusion, this study suggests that SAL can alleviate oxidative stress and renal fibrosis by inhibiting the activation of AGEs-mediated RAGE/JAK1/STAT3 signaling axis, thus playing a potential role in the treatment of DN.

Therapeutic potential of salidroside in preserving rat cochlea organ of corti from gentamicin-induced injury through modulation of NRF2 signaling and GSK3β/NF-κB pathway.

Salidroside (SAL) is a phenol glycoside compound found in plants of the Rhodiola genus which has natural antioxidant and free radical scavenging properties. SAL are able to protect against manganese-induced ototoxicity. However, the molecular mechanism by which SAL reduces levels of reactive oxygen species (ROS) is unclear. Here, we established an in vitro gentamicin (GM) ototoxicity model to observe the protective effect of SAL on GM-induced hair cells (HC) damage. Cochlear explants of postnatal day 4 rats were obtained and randomly divided into six groups: two model groups (treatment with 0.2 mM or 0.4 mM GM for 24 h); two 400 μmol/L SAL-pretreated groups pretreatment with SAL for 3 h followed by GM treatment (0.2 mM or 0.4 mM) for 24 h; 400 μmol/L SAL group (treatment with SAL for 24 h); control group (normal cultured cochlear explants). The protective effects of SAL on GM-induced HC damage, and on mRNA and protein levels of antioxidant enzymes were observed. HC loss occurred after 24 h of GM treatment. Pretreatment with SAL significantly reduced GM-induced OHC loss. In cochlear tissues, mRNA and protein levels of NRF2 and HO-1 were enhanced in the GM alone group compared with the SAL pretreatment GM treatment group. SAL may protect against GM-induced ototoxicity by regulating the antioxidant defense system of cochlear tissues; SAL can activate NRF2/HO-1 signaling, inhibit NF-κB activation, activate AKT, and increase inhibitory phosphorylation of GSK3β to decrease GSK3 activity, all of which exert antioxidant effects.

Salidroside protects RGC from pyroptosis in diabetes-induced retinopathy associated with NLRP3, NFEZL2 and NGKB1, revealed by network pharmacology analysis and experimental validation

ObjectiveTo investigate the effect of salidroside (SAL) in protecting retinal ganglion cell (RGC) from pyroptosis and explore associated molecular network mechanism in diabetic retinapathy (DR) rats.MethodsHE, Nissl and immunofluorescence staining were used to observe the retinal morphological change, and the related target genes for salidroside, DR and pyroptosis were downloaded from GeneCard database. Then Venny, PPI, GO, KEGG analysis and molecular docking were used to reveal molecular network mechanism of SAL in inhibiting the pyroptosis of RGC. Lastly, all hub genes were confirmed by using qPCR.ResultsHE and Nissl staining showed that SAL could improve the pathological structure known as pyroptosis in diabetic retina, and the fluorescence detection of pyroptosis marker in DM group was the strongest, while they decreased in the SAL group(P < 0.05)). Network pharmacological analysis showed 6 intersecting genes were obtained by venny analysis. GO and KEGG analysis showed 9 biological process, 3 molecular function and 3 signaling pathways were involved. Importantly, molecular docking showed that NFE2L2, NFKB1, NLRP3, PARK2 and SIRT1 could combine with salidroside, and qPCR validates the convincible change of CASP3, NFE2L2, NFKB1, NLRP3, PARK2 and SIRT1.ConclusionSalidroside can significantly improve diabetes-inducedRGC pyrotosis in retina, in which, the underlying mechanism is associated with the NLRP3, NFEZL2 and NGKB1 regulation.

Neuroprotective effect of salidroside on hippocampal neurons in diabetic mice via PI3K/Akt/GSK-3β signaling pathway.

Diabetic encephalopathy is manifested by cognitive dysfunction. Salidroside, a nature compound isolated from Rhodiola rosea L, has the effects of anti-inflammatory and antioxidant, hypoglycemic and lipid-lowering, improving insulin resistance, inhibiting cell apoptosis, and protecting neurons. However, the mechanism by which salidroside alleviates neuronal degeneration and improves learning and memory impairment in diabetic mice remains unclear. To investigate the effects and mechanisms of salidroside on hippocampal neurons in streptozotocin-induced diabetic mice. C57BL/6 mice were randomly divided into 4 groups to receive either sham (control group (CON)), diabetes mellitus (diabetes group (DM)), diabetes mellitus + salidroside (salidroside group (DM + SAL)), and diabetes mellitus + salidroside + phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 (diabetes mellitus + salidroside + LY294002 group (DM + SAL + LY294002)). After 12weeks of diabetes onset, the cognitive behaviors were tested using Morris water maze. The number of hippocampal neurons was detected by Nissl staining. The expressions of PI3K, p-PI3K, Akt, p-Akt, GSK-3β, p-GSK-3β, cleaved caspase-3, caspase-3, Bax, Bcl-2, MAP2, and SYN in the hippocampus were detected by Western blot. Moreover, the expression of MAP2 and SYN in the hippocampus was further confirmed by immunofluorescence staining. Salidroside increased the time of diabetic mice in the platform quadrant and reduced the escape latency of diabetic mice. Salidroside also increased the expression of p-PI3K, p-Akt, p-GSK-3β, MAP2, SYN, Bcl-2, while suppressed the expression of cleaved caspase-3, caspase3, and Bax in the DM + SAL group compared with the DM group (P < 0.05). The Nissl staining showed thatthe number of hippocampus neurons in the DM + SAL group was increased with the intact, compact, and regular arrangement, compared with the DM groups (P < 0.05). Interestingly, the protective effects of salidroside on diabetic cognitive dysfunction, hippocampal morphological alterations, and protein expressions were abolished by inhibition of PI3K with LY294002. Salidroside exerts neuroprotective properties in diabetic cognitive dysfunction partly via activating the PI3K/Akt/GSK-3β signaling pathway.

Reshaped Gut Microbial Composition and Functions Associated with the Antifatigue Effect of Salidroside in Exercise Mice.

Salidroside (SA) is an active compound derived from Rhodiola rosea and is widely used in healthcare foods. However, the underlying mechanism and its specific role in regulating the gut microbial community during exercise (Ex) remains unknown. Mice are subjected to a weight-loaded swimming test (WST) Ex to determine how gut microbiota affects the antifatigue activity of SA. The SA-treated group mice (100mgkg-1 .bw.) display a significant increase in swimming time compared to the control group (26.2 versus 10.5min, p<0.01), as well as an increase in respiratory enzymatic activities after swimming. The respiratory enzymatic activities are significantly higher in the SA-treated group than in the RS (regular rest) group after swimming. The bacteria profiles in the Ex+SA group change significantly with higher species diversity and abundance. Receiver operating characteristic (ROC) curves of Alistipes, Rikenellaceae, Parabacteroides, Candidatus Arthromitus, and Lactobacillus indicate a high diagnostic utility to distinguish SA treatment. Microbial function analysis shows that SA may improve Ex-induced fatigue by modulating energy metabolism-related processes. SA demonstrates antifatigue effects on various levels of regulating energy metabolism and microbial composition, providing insights into the underlying mechanisms of SA as a natural prebiotic.

Salidroside attenuates LPS-induced inflammatory activation in young rats with acute lung injury via PI3K/Akt signaling pathway.

This experiment aimed to analyze the salidroside effect on lipopolysaccharide (LPS)-induced inflammatory activation in young rats with acute lung injury (ALI) via PI3K/Akt signaling pathway. In this study, sixty SD young rats were divided into 5 groups (control, model, salidroside low-dose, salidroside medium-dose and salidroside high-dose), with 12 rats in each group. ALI rat model was established. In the control and model group, rats were intraperitoneally injected with normal saline, while the salidroside low-, medium-, and high-dose groups were intraperitoneally injected with 5, 20, and 40 mg/kg salidroside, then the pathological changes of lung tissue, lung injury score, wet/dry lung weight ratio, neutrophils and TNF-α, MPO, MDA, NO, p-PI3K and p-AKT were detached and compared between these groups. Results showed that the ALI rat model was successfully established. The lung injury score, wet/dry lung weight ratio, neutrophils and TNF-α in alveolar lavage fluid, MPO, MDA, NO, p-PI3K and p-AKT in the lung tissue of the model group were increased than the control group. With the increase of salidroside dose, lung injury score, wet lung weight/dry lung weight ratio, neutrophils and TNF-α in alveolar lavage fluid, and the levels of MPO, MDA, NO, p-PI3K and p-AKT in lung tissues of the salidroside group were decreased then model group (P < 0.05). In conclusion, salidroside may reduce the activation of inflammatory cells in the lung tissue of young rats with LPS-induced ALI by activating PI3K/AKT signaling pathway, thereby exerting a certain protective effect on the lung tissue with LPS-induced ALI.

Salidroside Alleviates Renal Fibrosis in SAMP8 Mice by Inhibiting Ferroptosis.

Renal fibrosis progression is closely associated with aging, which ultimately leads to renal dysfunction. Salidroside (SAL) is considered to have broad anti-aging effects. However, the roles and mechanisms of SAL in aging-related renal fibrosis remain unclear. The study aimed to evaluate the protective effects and mechanisms of SAL in SAMP8 mice. SAMP8 mice were administered with SAL and Ferrostatin-1 (Fer-1) for 12 weeks. Renal function, renal fibrosis, and ferroptosis in renal tissue were detected. The results showed that elevated blood urea nitrogen (BUN) and serum creatinine (SCr) levels significantly decreased, serum albumin (ALB) levels increased, and mesangial hyperplasia significantly reduced in the SAL group. SAL significantly reduced transforming growth factor-β (TGF-β) and α-smooth muscle actin (α-sma) levels in SAMP8 mice. SAL treatment significantly decreased lipid peroxidation in the kidneys, and regulated iron transport-related proteins and ferroptosis-related proteins. These results suggested that SAL delays renal aging and inhibits aging-related glomerular fibrosis by inhibiting ferroptosis in SAMP8 mice.

Protective effects of salidroside on vascular endothelial cells in rats with frostbite after chronic hypoxia

Objective: To investigate the protective effects of salidroside on endothelial cells in rats with frostbite after chronic hypoxia. Methods: Healthy male SD rats, randomly divided into 3 groups with 10 rats in each group, which included the sham injury group, the model group, and the model +salidroside group. The rats in each group were placed in a composite low-pressure chamber to simulate a environment with a pressure of 54.1 kpa and a temperature of 23~25°C. The rats were exposed to hypoxia under these conditions for 14 days, during the experimental time the rats in the model+salidroside group were treated with 50 mg/kg salidroside daily. After the rats were removed from the low-pressure chamber, except for the sham injury group, frozen iron sheets were applied tightly to the back of the rats for 30 s, supplemented with low temperature for frostbite modeling. Blood and skin tissues were collected at 12 hours after modeling for testing. The structural changes in tissue and vascular endothelial cells were observed in the frostbite region. Vascular endothelial cell particulate EMP levels were detected. The levels of ICAM-1, sEPCR, vWF, ET-1 and NO secretion were determined. The expression levels of HIF-1α, p-PI3K, p-Akt and VEGF were detected by Western blot. Results: Salidroside could effectively reduce skin collapse in frostbitten areas. It could reduce the injury of frostbitten tissues, and improve the subcutaneous tissue necrosis and inflammatory cell infiltration. The autophagy of vascular endothelial cells was reduced. Compared with the model group (0.250±0.165)%, the expression of EMPs in the model+salidroside group (2.453±0.196)% was increased significantly (P＜0.01). In addition, the contents of NO (2.622±0.219)pg/ml was also significantly higher than that of the model group (1.616±0.152)pg/ml (P＜0.01), and the content of vWF (233.50±13.43)pg/ml was lower than that of the model group (315.60±8.78)pg/ml (P＜0.05). There was no significant difference in the levels of ICAM-1, sEPCR and ET-1. Salidroside significantly decreased the expressions of p-PI3K, p-Akt, VEGF and HIF-1α protein in vascular endothelial cells of rats with frostbite (P＜0.01). Conclusion: Salidroside can reduce endothelial cell damage, reduce endothelial cell autophagy and promote endothelial cell regeneration. Based on the PI3K/Akt pathway, salidroside has a good protective effect on endothelial cells of rats with frostbite after chronic hypoxia.

Gut microbiota profiling revealed the regulating effects of salidroside on iron metabolism in diabetic mice.

BackgroundDiabetes is a common metabolic disease that is associated with gut microbiota dysbiosis and iron metabolism. Salidroside (SAL) is the main ingredient of the traditional Chinese herb Rhodiola, previous studies have shown that SAL could reshape the gut microbiota and limit iron accumulation. Therefore, it is possible that SAL can act as an alternative therapy for diabetes, and its underlying mechanism is worth exploring.MethodsSAL was used to treat diabetic db/db mice. Serum glucose and iron levels and the histopathology of myocardial fibres were evaluated. The gut microbiota composition was determined by 16S rRNA Illumina sequencing technology.ResultsTreatment with SAL significantly reduced blood glucose and ameliorated diabetic cardiomyopathy in diabetic db/db mice, which was accompanied by inhibited ferroptosis and iron accumulation. Furthermore, the 16S rRNA sequencing results showed that SAL induced a change in the gut microbiota composition. Overall, SAL could increase the proportion of probiotic bacteria and decrease Lactobacillus to improve gut microbiota. Specifically, SAL increased the ratio of Bacteroidetes to Firmicutes in diabetic mice. The most significant biomarker was the genus Lactobacillus between the MD group and the SAL group. In addition, COG and KEGG analyses suggested that SAL mainly participated in nutrient metabolism, among them iron metabolism was associated with the abundance of Lactobacillus.ConclusionsSAL could reduce the glucose level and protect against diabetic cardiomyopathy in diabetic mice, which might be mediated by the change in the gut microbiota and the regulation of iron metabolism. The findings suggested that SAL was a promising complementary option for diabetes therapy.

Protective effect of salidroside on high fat-induced apoptosis in H9c2 cardiomyocytes through AMPK/mTOR/p70S6K pathway

The study explored the effect of salidroside(SAL) on high fat-induced apoptosis in H9 c2 cardiomyocytes based on AMPK/mTOR/p70 S6 K pathway.H9 c2 cardiomyocytes were cultured in vitro and the lipotoxicity model of H9 c2 cardiomyocytes was constructed by 0.2 mmol·L~(-1) palmitic acid(PA) treatment for 24 hours.The cells were divided into control group, PA group, and SAL group(20 μmol·L~(-1)).Cell proliferation was detected with cell proliferation kit I(MTT) assay after SAL and PA treatment.Dihydroethidium(DHE) probe, Annexin V-FITC/PI kit, and JC-1 probe were used to estimate reactive oxygen species(ROS) level, cell apoptosis, and mitochondrial membrane potential(MMP) change, respectively.The expression levels of p-AMPK/AMPK, p-mTOR/mTOR, p-p70 S6 K/p70 S6 K and apoptosis-related proteins Bax, Bcl-2, and cleaved caspase-3 were investigated with Western blot.The mRNA levels of AMPK, mTOR and p70 S6 K were determined by quantitative reverse transcription-polymerase chain reaction(qRT-PCR).RESULTS:: showed that compared with control group, PA group had decreased cell proliferation ability, MMP, Bcl-2 protein expression and AMPK protein and mRNA expression, while increased ROS level, Bax and cleaved caspase-3 protein expression, and mTOR and p70 S6 K mRNA and protein expression, and the difference was statistically significant(P&lt;0.05, P&lt;0.01).Compared with PA group, SAL improved cell proliferation ability, MMP level, Bcl-2 protein expression, and AMPK mRNA and protein expression, while down-regulated ROS level, cell apoptosis, Bax and cleaved caspase-3 protein expression, and mTOR and p70 S6 K mRNA and protein expression, and the difference was statistically significant(P&lt;0.05, P&lt;0.01).In conclusion, SAL exerted protective effects on high fat-induced lipotoxicity of H9 c2 cardiomyocytes, alleviated the oxidative stress injury and reduced cell apoptosis via regulating AMPK/mTOR/p70 S6 K signaling pathway.

Dietary supplementation of salidroside alleviates liver lipid metabolism disorder and inflammatory response to promote hepatocyte regeneration via PI3K/AKT/Gsk3-β pathway

Fatty liver hemorrhagic syndrome (FLHS) is a chronic hepatic disease which occurs when there is a disorder in lipid metabolism. FLHS is often observed in caged laying hens and characterized by a decrease in egg production and dramatic increase of mortality. Salidroside (SDS) is an herbal drug which has shown numerous pharmacological activities, such as protecting mitochondrial function, attenuating cell apoptosis and inflammation, and promoting antioxidant defense system. We aimed to determine the therapeutic effects of SDS on FLHS in laying hens and investigate the underlying mechanisms through which SDS operates these functions. We constructed oleic acid (OA)-induced fatty liver model in vitro and high-fat diet-induced FLHS of laying hens in vivo. The results indicated that SDS inhibited OA-induced lipid accumulation in chicken primary hepatocytes, increased hepatocyte activity, elevated the mRNA expression of proliferation related genes PCNA, CDK2, and cyclinD1 and increased the protein levels of PCNA and CDK2 (P < 0.05), as well as decreased the cleavage levels of Caspase-9, Caspase-8, and Caspase-3 and apoptosis in hepatocytes (P < 0.05). Moreover, SDS promoted the phosphorylation levels of PDK1, AKT, and Gsk3-β, while inhibited the PI3K inhibitor (P < 0.05). Additionally, we found that high-fat diet-induced FLHS hens had heavier body weight, liver weight, and abdominal fat weight, and severe steatosis in histology, compared with the control group (Con). However, hens fed with SDS maintained lighter body weight, liver weight, and abdominal fat weight, as well as normal liver without hepatic steatosis. In addition, high-fat diet-induced FLHS hens had high levels of serum total cholesterol (TC), triglyceride (TG), alanine transaminase (ALT), and aspartate aminotransferase (AST) compared to the Con group, however, in the Model+SDS group, the levels of TC, TG, ALT, and AST decreased significantly, whereas the level of superoxide dismutase (SOD) increased significantly (P < 0.05). We also found that SDS significantly decreased the mRNA expression abundance of PPARγ, SCD, and FAS in the liver, as well as increased levels of PPARα and MTTP, and decreased the mRNA expression of TNF-α, IL-1β, IL-6, and IL-8 in the Model+SDS group (P < 0.05). In summary, this study showed that 0.3 mg/mL SDS attenuated ROS generation, inhibited lipid accumulation and hepatocyte apoptosis, and promoted hepatocyte proliferation by targeting the PI3K/AKT/Gsk3-β pathway in OA-induced fatty liver model in vitro, and 20 mg/kg SDS alleviated high-fat-diet-induced hepatic steatosis, oxidative stress, and inflammatory response in laying hens in vivo.

Salidroside suppresses the activation of nasopharyngeal carcinoma cells via targeting miR-4262/GRP78 axis

ABSTRACT To study the effect of Salidroside on nasopharyngeal carcinoma (NPC) cells and its mechanism. NPC cells were cultured, MTT was used to detect the effect of Salidroside on cell proliferation, apoptosis detected by flow cytometry assay, Western blot was used to detect the related protein expression. MiR-4262 and GRP78 used qRT-PCR for evaluation. Mimics/mimic NC and miR-4262 inhibitor/inhibitor NC were transfected into CNE2 and HONE1 cell lines, and cell viability was detected by MTT. Caspase-3, −8 and −9 activities were detected by caspase colorimetric assay kit. Targetscan predicted that downstream target of miR-4262. Relative luciferase activity was detected by luciferase assay. The effect of Salidroside on the growth of transplanted tumor in nude mice was observed. After Salidroside treatment, cell proliferation decreased and apoptosis increased, Bax protein expression increased and Bcl-2 decreased; miR-4262 expression level in nasopharyngeal carcinoma tissues was lower than that in adjacent tissues. GRP78 was the target of miR-4262 and downregulate the expression of miR-4262 in NPC cells can increase the expression of GRP78, and the expression of GRP78 decreased after upregulating the expression of miR-4262. Salidroside could inhibit the growth of NPC xenografts in nude mice. The level of Bax was increased and Bcl-2 was decreased in Salidroside group. Salidroside can significantly inhibit the proliferation and promote the apoptosis of NPC cells via regulating miR-4262/GRP78 signal axis.

Study on mechanism of salidroside against liver fibrosis by regulating CXCL16

In order to investigate the effect of salidroside on inhibiting liver fibrosis and its relationship with CXC chemokine ligand 16(CXCL16) in vivo and in vitro, totally 45 C57 BL/6 J male mice were randomly divided into normal group, model group and salidroside group, with 15 mice in each group. The mice in model group and salidroside group were injected intraperitoneally with 15% carbontetrachloride(CCl_4) olive oil solution to establish liver fibrosis model, and the mice in normal group were injected intraperitoneally with the same dose of olive oil. Salidroside group was given with 100 mg·kg~(-1 )salidroside by gavage, while the normal group and model group received the same amount of double distilled water by gavage. All mice were sacrificed after 5 weeks of intragastric administration. The pathological changes of mouse liver were observed by hematoxylin-eosin(HE) staining, and the degree of liver fibrosis was observed by sirius red staining. The protein expressions of collagen Ⅰ(ColⅠ), α-smooth muscle actin(α-SMA), fibronectin(FN), CXCL16, phosphorylated Akt(p-Akt), Akt in liver tissues were detected by Western blot. Hepatic stellate cell line JS 1 was cultured in vitro and divided into control group, model group(100 μg·L~(-1) CXCL16) and salidroside group(100 μg·L~(-1) CXCL16+1×10~(-5) mol·L~(-1) salidroside). Cell migration was detected by cell scratch, the mRNA expressions of ColⅠ and α-SMA were detected by RT-PCR, and the protein expressions of p-Akt and Akt were detected by Western blot. As compared with the normal group, the protein expressions of ColⅠ, α-SMA, FN, CXCL16, and p-Akt in the model group were significantly increased, and salidroside could reduce the expression of these indicators(P&lt;0.05 or P&lt;0.01). In vitro, CXCL16 could promote the migration of JS 1, increase the mRNA expressions of ColⅠ and α-SMA in JS 1, and enhance Akt phosphorylation in JS 1(P&lt;0.05 or P&lt;0.01). As compared with the model group, salidroside could inhibit the migration of JS 1 induced by CXCL16(P&lt;0.05), and reduce the high expression of ColⅠ and α-SMA mRNA and the phosphorylation of Akt in JS 1 induced by CXCL16(P&lt;0.05). In conclusion, salidroside might attenuate CCl_4-induced liver fibrosis in mice by inhibiting the migration, activation and Akt phosphorylation of hepatic stellate cells induced by CXCL16.

Enhanced effects of salidroside on erectile function and corpora cavernosa autophagy in a cavernous nerve injury rat model.

We explored the efficacy and mechanisms of salidroside treatment for erectile dysfunction induced by bilateral cavernous nerve injury (BCNI). Forty male rats were divided into four groups as follows: sham (cavernous nerves exposed only) (S); BCNI (M); BCNI+rapamycin (M+rapamycin); and BCNI+salidroside (M+salidroside). Erectile function in the rats was measured by intracavernosal pressure. Penile tissue was harvested for transmission electron microscopy, immunohistochemistry, immunofluorescence, Masson's trichrome staining, haematoxylin-eosin staining, TdT-mediated dUTP Nick End Labeling and western blotting. The M group exhibited a decrease in erectile responses and increased apoptosis and fibrosis compared to these in the S group. Meanwhile, nerve content and the penile atrophy index were also decreased in the M group. Treatment with salidroside and rapamycin for 3weeks partially restored erectile function and significantly attenuated corporal apoptosis, fibrosis, nerve content and penile atrophy in the M group. Moreover, the autophagy level was further enhanced in the M+salidroside group, which was the same as that in the positive observation group (M+rapamycin). Salidroside treatment not only improved erectile function in rats with BCNI, but also inhibited apoptosis and fibrosis and ameliorated the loss of nerve content and endothelial and corpus cavernosum smooth muscle cells by promoting protective autophagy.

Inhibitory effects of salidroside on MCF-7 breast cancer cells in vivo.

ObjectiveWe investigated the antitumor effects of salidroside and preliminarily examined its underlying mechanisms by establishing a nude mouse model bearing MCF-7 breast cancer cell xenografts.MethodsThe mice were grouped and intraperitoneally injected with salidroside, paclitaxel, or physiological saline. Tumor samples were weighed, and immunohistochemical staining with hematoxylin and eosin and anti-CD34 antibody was performed. Tumor cell apoptosis was observed using the terminal deoxynucleotidyl transferase deoxyuridine dUTP nick end labeling assay. Bcl-1, p53, Bax, and caspase 3 expression in tumor tissues was determined via western blotting.ResultsThe tumor inhibition rate of high-dose salidroside was 75.16%, which was significantly higher than the rates for paclitaxel and saline. A tumor tissue pathology analysis revealed that high-dose salidroside inhibited tumor cell proliferation and promoted tumor cell apoptosis. Western blotting revealed that Bcl-2 and p53 expression were significantly lower in the salidroside group than in the other groups, whereas Bax and caspase 3 (17 kDa) expression were increased.ConclusionsSalidroside was more effective than paclitaxel in inhibiting tumor growth in MCF-7 breast cancer cell-bearing nude mice. The mechanism of action may involve Bcl-2 and p53 downregulation and Bax and caspase 3 upregulation, thereby increasing proapoptotic factor expression and inducing tumor cell apoptosis.

Mechanism of salidroside relieving the acute hypoxia-induced myocardial injury through the PI3K/Akt pathway.

ObjectiveThe objective was to investigate the anti-inflammatory effects of salidroside through the PI3K/Akt signaling pathway and its protective effects on acute hypoxia-induced myocardial injury in rats.MethodsA total of 24 healthy Sprague-Dawley male rats were selected as the experimental subjects. All rats were divided into 4 groups by using the random number table method, with 6 rats in each group. The groups included the normal control group, the salidroside group, the hypobaric hypoxia group, and the hypobaric hypoxia + salidroside group. Rats in the salidroside group were fed in the original animal laboratory and were intragastrically administered with salidroside every morning at a dosage of 35 mg/kg. Rats in the normal control group were intragastrically administered with an equal dosage of saline. Rats in the hypobaric hypoxia + salidroside group were intragastrically administered with salidroside every morning at a dosage of 35 mg/kg, who were fed in the hypoxic experiment module for animals. The altitude was increased to 4000 m, and the rats were kept in the module for 24 h. Rats in the hypobaric hypoxia group were intragastrically administered with an equal dosage of saline in the same environment, and the altitude was increased to 4000 m after administration. Parameters of blood gas analysis, histopathological changes in cardiac tissues, cardiac indexes, and inflammatory factors IL-6 and TNF-α levels of rats in groups were compared.Results1. The cardiac indexes of rats in groups were compared. The differences between the hypobaric hypoxia group and the hypobaric hypoxia + salidroside group were statistically significant (P < 0.05). 2. The results of blood gas analysis of rats in groups were compared. The differences between the hypobaric hypoxia group and the hypobaric hypoxia + salidroside group were significantly different (P < 0.05). 3. In the hypobaric hypoxia group, the myocardial cells of rats were arranged disorderly and shaped differently, with cases such as edema, degeneration, necrosis, nucleus pyknosis, and massive infiltration of inflammatory cells. In the hypobaric hypoxia + salidroside group, the above-mentioned pathological changes in myocardial cells were relieved. 4. Compared with the hypobaric hypoxia group, in the hypobaric hypoxia + salidroside group, the concentrations of IL-6 and TNF-α in rats decreased apparently, and the differences were statistically significant (P < 0.05).ConclusionSalidroside had the repairing and protective effects on the hypobaric hypoxia-induced myocardial injuries in rats. The application of salidroside could reduce the inflammatory responses of rats with hypobaric hypoxia-induced myocardial injuries through PI3K/Akt signaling pathway, thereby protecting the myocardial cells.

Protective effects of salidroside on chronic heart failure in rats and the underlying mechanisms

The present study aimed to investigate the protective effects of salidroside on chronic heart failure (CHF) in rats and to explore the underlying mechanisms. One hundred SD rats were randomly divided into sham-operated, model, and low-, medium- and high-dose salidroside groups. The CHF model was established in later 4 groups. The later 3 groups were intragastrically administrated with 6, 12 and 24 mg/kg salidroside, respectively, once a day, for continuous 4 weeks. Finally, the serum levels of brain natriuretic peptide (BNP) and interleukin 6 (IL-6), cardiac function indexes, and expression levels of myocardial cysteinyl aspartate-specific proteinase (Caspase)-3, Caspase-9, matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinase-1 (TIMP-1) protein were determined. Results showed that, after treatment, compared with model group, in high-dose salidroside group the heart function indexes were significantly improved (P < 0.05), the serum levels of BNP and IL-6 were significantly decreased (P < 0.05), the expression levels of myocardial Caspase-3, Caspase-9 and MMP-1 protein were significantly decreased (P < 0.05), and the expression level of TIMP-1 protein was significantly increased (P < 0.05). In conclusion, salidroside has obvious protective effects on CHF in rats. The mechanisms may be related to its regulation of cardiomyocyte apoptosis and ventricular remodelingregulation related protein expressions.

Salidroside prevents skin carcinogenesis induced by DMBA/TPA in a mouse model through suppression of inflammation and promotion of apoptosis.

Salidroside (SR) is a main component of Rhodiola rosea L. and exhibits a variety of pharmacologic properties. The present study was carried out to explore the potential effect of SR against skin cancer induced by 7,12-dimethylbenz(a)anthracene (DMBA) and 12-O-tetradecanoylphorbol-13-acetate (TPA) in female Institute for Cancer Research (ICR) mice and to reveal the underlying molecular targets regulated by SR. The mice were randomly divided into 4 groups: control, DMBA/TPA, DMBA/TPA+SR (20 mg/kg) and DMBA/TPA+SR (40 mg/kg). SR was administered to mice five times a week after DMBA treatments. In our study, we found that SR dose-dependently ameliorated skin cancer incidence and the multiplicity in the animal models by reducing the release of inflammation-related cytokines, including tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), interleukin-18 (IL-18), interleukin-6 (IL-6), cyclooxygenase 2 (COX2) and transforming growth factor β-1 (TGF-β1). Suppression of the nuclear factor (NF)-κB signaling pathway by SR was effective to prevent skin carcinogenesis. Furthermore, TUNEL analysis indicated that compared to the DMBA/TPA group, enhanced apoptosis was observed in the DMBA/TPA+SR group. In addition, p53 expression levels were increased by SR in the DMBA/TPA-induced mice. Therefore, SR was effective for inducing apoptosis during skin cancer progression triggered by DMBA/TPA. Consistently, p21, p53 upregulated modulator of apoptosis (PUMA), Bax and caspase-3 were highly induced by SR to enhance the apoptotic response for preventing skin cancer. Moreover, in vitro, we found that SR dramatically reduced the inflammatory response, while enhancing the aoptotic response by blocking NF-κB and activating caspase-3 pathways, respectively. In addition, flow cytometric analysis further confirmed the induction of apoptosis by SR in DMBA-treated cells in vitro. Taken together, the in vivo and in vitro studies illustrated that SR might be a promising compound to reduce skin cancer risk.

Salidroside attenuates hypoxia-induced pulmonary arterial smooth muscle cell proliferation and apoptosis resistance by upregulating autophagy through the AMPK-mTOR-ULK1 pathway

BackgroundRecent studies have shown that both adenosine monophosphate activated protein kinase (AMPK) and the mammalian target of rapamycin (mTOR) are energy sensors and are related to autophagy. Our recent reports have shown that salidroside can exert protective effects against hypoxia-induced pulmonary arterial smooth muscle cell (PASMC) proliferation and apoptosis resistance through the AMPK pathway. This study aims to explore the relationship among AMPK, mTOR and ULK1 in PASMCs under hypoxic conditions and to investigate whether the protective effects of salidroside are related to the autophagic cell death pathway.MethodsRat PASMCs were cultured and divided into five groups: the normoxia, hypoxia, hypoxia + MHY1485 (mTOR agonist), hypoxia + rapamycin (mTOR inhibitor) and hypoxia + salidroside groups. Hypoxic cells were treated as indicated for 24 h. Cell viability was evaluated by the CCK-8 assay. Cell apoptosis was measured by the TUNEL assay. The autophagy flux of PASMCs was evaluated with tandem mRFP-GFP fluorescence microscopy. Autophagosomes were detected by electron microscopy. Protein expression of LC3, p62, AMPK, P-AMPK (Thr 172), P-ULK1 (Ser 555 and Ser 317), mTOR, P-mTOR (Ser 2448), ULK1 and P-ULK1 (Ser 757) was detected by western blot assay.ResultsPASMC proliferation and apoptosis resistance were observed under hypoxic conditions. Autophagy flux, the number of autophagosomes and the LC3II/LC3I ratio were increased in the hypoxia group compared with the normoxia group, whereas p62 expression was decreased. Treatment with rapamycin or salidroside reversed hypoxia-induced PASMC proliferation and apoptosis resistance and further increased autophagy flux, autophagosome levels and the LC3II/LC3I ratio but decreased p62 expression. Treatment with MHY1485 reversed hypoxia-induced PASMC apoptosis resistance and decreased autophagy flux as well as increased autophagosome levels, the LC3II/LC3I ratio and p62 expression. P-AMPK (Thr 172) and P-ULK1 (Ser 555) of the AMPK-ULK1 pathway were increased in the hypoxia group and were further increased in the salidroside group. Rapamycin and MHY1485 had no effect on either P-AMPK (Thr 172) or P-ULK1 (Ser 555). Phosphorylation of ULK1 at serine 317 did not significantly affect the five groups. Furthermore, P-mTOR (Ser 2448) and P-ULK1 (Ser 757) of the AMPK-mTOR-ULK1 pathway were decreased in the hypoxia group and were further decreased in the salidroside group. MHY1485 increased the expression of both P-mTOR(Ser 2448) and P-ULK1(Ser 757), whereas rapamycin had the opposite effect.ConclusionsSalidroside might inhibit hypoxia-induced PASMC proliferation and reverse apoptosis resistance via the upregulation of autophagy through both the AMPKα1-ULK1 and AMPKα1-mTOR-ULK1 pathways.