Diosgenin Group Research Articles

Diosgenin alleviates NAFLD induced by a high-fat diet in rats via mTOR/SREBP-1c/HSP60/MCAD/SCAD signaling pathway

This study aims to observe the effects of diosgenin on the expression of mammalian target of rapamycin(mTOR), sterol regulatory element-binding protein-1c(SREBP-1c), heat shock protein 60(HSP60), medium-chain acyl-CoA dehydrogenase(MCAD), and short-chain acyl-CoA dehydrogenase(SCAD) in the liver tissue of the rat model of non-alcoholic fatty liver disease(NAFLD) and explore the mechanism of diosgenin in alleviating NAFLD. Forty male SD rats were randomized into five groups: a control group, a model group, low-(150 mg·kg~(-1)·d~(-1)) and high-dose(300 mg·kg~(-1)·d~(-1)) diosgenin groups, and a simvastatin(4 mg·kg~(-1)·d~(-1)) group. The rats in the control group were fed with a normal diet, while those in the other four groups were fed with a high-fat diet. After feeding for 8 weeks, the body weight of rats in the high-fat diet groups increased significantly. After that, the rats were administrated with the corresponding dose of diosgenin or simvastatin by gavage every day for 8 weeks. The levels of triglyceride(TG), total cholesterol(TC), alanine transaminase(ALT), and aspartate transaminase(AST) in the serum were determined by the biochemical method. The levels of TG and TC in the liver were measured by the enzyme method. Oil-red O staining was employed to detect the lipid accumulation, and hematoxylin-eosin(HE) staining to detect the pathological changes in the liver tissue. The mRNA and protein levels of mTOR, SREBP-1c, HSP60, MCAD, and SCAD in the liver tissue of rats were determined by real-time fluorescence quantitative polymerase chain reaction(RT-qPCR) and Western blot, respectively. Compared with the control group, the model group showed increased body weight, food uptake, liver index, TG, TC, ALT, and AST levels in the serum, TG and TC levels in the liver, lipid deposition in the liver, obvious hepatic steatosis, up-regulated mRNA and protein expression levels of mTOR and SREBP-1c, and down-regulated mRNA and protein expression levels of HSP60, MCAD, and SCAD. Compared with the model group, the rats in each treatment group showed obviously decreased body weight, food uptake, liver index, TG, TC, ALT, and AST levels in the serum, TG and TC levels in the liver, lessened lipid deposition in the liver, ameliorated hepatic steatosis, down-regulated mRNA and protein le-vels of mTOR and SREBP-1c, and up-regulated mRNA and protein levels of HSP60, MCAD, and SCAD. The high-dose diosgenin outperformed the low-dose diosgenin and simvastatin. Diosgenin may prevent and treat NAFLD by inhibiting the expression of mTOR and SREBP-1c and promoting the expression of HSP60, MCAD, and SCAD to reduce lipid synthesis, improving mitochondrial function, and promoting fatty acid β oxidation in the liver.

Effect of diosgenin on mTOR/FASN/HIF-1α/VEGFA expression in rats with non-alcoholic fatty liver disease

The present study aimed to investigate the effect of diosgenin on mammalian target of rapamycin(mTOR), fatty acid synthase(FASN), hypoxia inducible factor-1α(HIF-1α), and vascular endothelial growth factor A(VEGFA) expression in liver tissues of rats with non-alcoholic fatty liver disease(NAFLD) and explore the mechanism of diosgenin on lipogenesis and inflammation in NAFLD. Forty male SD rats were divided into a normal group(n=8) fed on the normal diet and an experimental group(n=32) fed on the high-fat diet(HFD) for the induction of the NAFLD model. After modeling, the rats in the experimental group were randomly divided into an HFD group, a low-dose diosgenin group(150 mg·kg~(-1)·d~(-1)), a high-dose diosgenin group(300 mg·kg~(-1)·d~(-1)), and a simvastatin group(4 mg·kg~(-1)·d~(-1)), with eight rats in each group. The drugs were continuously given by gavage for eight weeks. The levels of triglyceride(TG), total cholesterol(TC), low-density lipoprotein cholesterol(LDL-C), alanine transaminase(ALT), and aspartate transaminase(AST) in the serum were detected by the biochemical method. The content of TG and TC in the liver was detected by the enzyme method. Enzyme-linked immunosorbent assay(ELISA) was used to measure interleukin 1β(IL-1β) and tumor necrosis factor α(TNF-α) in the serum. Lipid accumulation in the liver was detected by oil red O staining. Pathological changes of liver tissues were detected by hematoxylin-eosin(HE) staining. The mRNA and protein expression levels of mTOR, FASN, HIF-1α, and VEGFA in the liver of rats were detected by real-time fluorescence-based quantitative polymerase chain reaction(PCR) and Western blot, respectively. Compared with the normal group, the HFD group showed elevated body weight and levels of TG, TC, LDL-C, ALT, AST, IL-1β, and TNF-α(P<0.01), increased lipid accumulation in the liver(P<0.01), obvious liver steatosis, up-regulated mRNA expression levels of mTOR, FASN, HIF-1α, and VEGFA(P<0.01), and increased protein expression levels of p-mTOR, FASN, HIF-1α, and VEGFA(P<0.01). Compared with the HFD group, the groups with drug treatment showed lowered body weight and levels of TG, TC, LDL-C, ALT, AST, IL-1β, and TNF-α(P<0.05, P<0.01), reduced lipid accumulation in the liver(P<0.01), improved liver steatosis, decreased mRNA expression levels of mTOR, FASN, HIF-1α, and VEGFA(P<0.05, P<0.01), and declining protein expression levels of p-mTOR, FASN, HIF-1α, and VEGFA(P<0.01). The therapeutic effect of the high-dose diosgenin group was superior to that of the low-dose diosgenin group and the simvastatin group. Diosgenin may reduce liver lipid synthesis and inflammation and potentiate by down-regulating the mTOR, FASN, HIF-1α, and VEGFA expression, playing an active role in preventing and treating NAFLD.

Diosgenin reduces bone loss through the regulation of gut microbiota in ovariectomized rats

Diosgenin (DIO) is an aglycone of steroid saponins acquired from plants, including Dioscorea alata, Smilax China, and Trigonella foenum graecum, acting as an anti-osteoporosis, anti-diabetic, anti-hyperlipidemic, anti-inflammatory. Recent studies have demonstrated that DIO reduces bone loss. This study aimed to investigate the effects of DIO on the gut microbiota (GM) of ovariectomized (OVX) osteoporotic rats. Female Sprague-Dawley rats were randomly divided into sham operation (sham + vehicle group) or ovariectomy. For 12 weeks, OVX rats were treated using a vehicle (OVX + vehicle group) and DIO (OVX + DIO group). Subsequently, ELISA was conducted to determine serum estradiol levels, micro-CT scanning was performed to evaluate bone quality, and feces were collected for metagenomics sequencing to examine the structure and function of GM. Raw reads were filtered to remove chimera sequences. Operational taxonomic units (OTUs) were clustered in the filtered reads. A Venn diagram analysis was conducted to study the common and unique OTUs in the sham + vehicle, OVX + vehicle, and OVX + DIO groups. LEfSe analysis was conducted to evaluate the specific GM of the three groups. The GM functions were analyzed using the KEGG and CAZy databases. After a 12-week treatment, DIO administration prevented OVX-induced weight gain and increased the estradiol levels. DIO treatment improved the bone microstructure and structural parameters of rat tibias. Metagenomics sequencing results identified 1139, 1207, and 1235 operational taxonomic units (OTUs) in the sham + vehicle, OVX + vehicle, and OVX + DIO groups, respectively. The percentage of common OTUs was 41.2%. Treatment with DIO restored the composition of GM in OVX rats by increasing the abundance of Coriobacteriia Adlercreutzia, Romboutsia, and Romboutsia_idealis and reducing the abundance of Betaproteobacteria, Gammaproteobacteria, Methanobacteria, Bacteroides, Phocaeicola, Alistipes, Bacteroids_uniformis, Bacteroids_xylanisolvens. The anti-osteoporosis effect of DIO can be regulated through environmental information processing, organismal Systems, Cellular Processes, human diseases, metabolism, and genetic information processing. Meanwhile, treatment with DIO improved GM homeostasis by increasing the metabolism of carbohydrates, other amino acids, and glycans and reducing translation, energy metabolism, and nucleotide metabolism. DIO can reduce bone loss by regulating the structural composition and function of GM, a novel strategy for preventing osteoporosis.

Study on the Mechanism of Diosgenin Targeting STAT3 to Inhibit Colon Cancer Proliferation and Migration.

To elucidate regulatory effects and molecular mechanisms of diosgenin on colon cancer, this study administered diosgenin at concentrations of 10 (low), 50 (medium), and 100 μmol/L (high concentration group) at the cell level, respectively. EdU, colony formation, and Transwell assays were implemented to determine SW480 cellular proliferation and migration. Assays of flow cytometry and TUNEL were employed to estimate cell apoptosis. Additionally, nude mouse tumorigenesis assay was used to further verify the regulatory function of diosgenin on colon cancer. The target protein of diosgenin was predicted via molecular docking. The results showed that all three concentrations of diosgenin could reduce colon cancer cellular proliferation and migration, and after diosgenin treatment, colon cancer cellular apoptosis was markedly increased, and the 100 μmol/L diosgenin group produced the most satisfactory inhibition on colon cancer cell proliferation. Ki67 expression was markedly reduced whereas those of Bax and caspase3 were greatly increased after diosgenin treatment. The nude mouse tumorigenesis assay indicated that the parameters of tumorous volume and mass of diosgenin treatment group were greatly decreased as compared to control, and as the concentration of diosgenin increased, the inhibitory effect was more significant. Molecular docking indicated that STAT3 served as a target protein of diosgenin. Moreover, after diosgenin treatment on colon cancer cells, the STAT3 expression was markedly reduced. The STAT3 overexpression would counteract the inhibitory effect of 50 μmol/L diosgenin in both suppressing colon cancer cellular proliferation and migration and promoting apoptosis. Taken together, all our outcomes demonstrated the diosgenin effects in not only inhibiting colon cancer cellular proliferation and migration but also promoting cancerous cellular apoptosis. Diosgenin is a regulatory player in targeting and regulating STAT3.

Transcriptome analysis of the effect of diosgenin on autoimmune thyroiditis in a rat model

In a mouse model of Graves’ disease (GD), diosgenin has been shown to have a therapeutic effect on GD by alleviating goitre. However, research on the effect of diosgenin on autoimmune thyroiditis (AIT) is lacking. In this study, transcriptomics was used to comprehensively analyse the protective effect of diosgenin against AIT in rats and the possible mechanism. The results showed that in the diosgenin-intervention group, compared to the model group, the expression of serum triiodothyronine, thyroxine, free triiodothyronine, and free thyroxine was decreased and that of thyroid-stimulating hormone was increased; these changes were accompanied by the downregulation of thyroglobulin, TSH receptor antibody and thyroid peroxidase expression in serum. Furthermore, transcriptome detection, RT-qPCR and immunohistochemistry verification revealed that in thyroid tissue, the relative mRNA and protein expression of cyclic adenosine 3′,5′-monophosphate (cAMP), protein kinase A (PKA) and cAMP response element-binding protein (Creb) were increased and the mRNA expression of S100 calcium-binding protein A9 (S100A9) was decreased in the diosgenin groups. In summary, diosgenin alleviates the development of AIT, possibly via the activation of the cAMP/PKA/Creb pathway and downregulation of S100A9 gene expression.

Diosgenin alleviates hypercholesterolemia via SRB1/CES-1/CYP7A1/FXR pathway in high-fat diet-fed rats

Phytosterol diosgenin (DG) exhibits cholesterol-lowering properties. Few studies focused on the underlying mechanism of DG attenuation of hypercholesterolemia by promoting cholesterol metabolism. To investigate the roles of SRB1/CES-1/CYP7A1/FXR pathways in accelerating cholesterol elimination and alleviating hypercholesterolemia, a rat model of hypercholesterolemia was induced by providing a high-fat diet (HFD). Experimental rat models were randomly divided into a normal control (Con) group, HFD group, low-dose DG (LDG) group (150 mg/kg/d), high-dose DG (HDG) group (300 mg/kg) and Simvastatin (Sim) group (4 mg/kg/d). Body weights, serum and hepatic lipid parameters of rats were tested. The expression levels of scavenger receptor class B type I (SRB1), carboxylesterase-1 (CES-1), cholesterol7α- hydroxylase (CYP7A1), and farnesoid X receptor (FXR) were determined. The results showed that DG reduced weight and lowered lipid levels in HFD-fed rats. Pathological morphology analyses revealed that DG notably improved hepatic steatosis and intestinal structure. Further studies showed the increased hepatic SRB1, CES-1, CYP7A1 and inhibited FXR-mediated signaling in DG-fed rats, which contributing to the decrease of hepatic cholesterol. DG also increased intestinal SRB1 and CES-1, inhibiting cholesterol absorption and promoting RCT. The expression levels of these receptors in the HDG group were higher than LDG and Sim groups. These data suggested that DG accelerated reverse cholesterol transport (RCT) and enhanced cholesterol elimination via SRB1/CES-1/CYP7A1/FXR pathway, and DG might be a new candidate for the alleviation of hypercholesterolemia.

Regulatory effect of diosgenin on lipogenic genes expression in high-fat diet-induced obesity in mice.

Obesity is one of the most serious health problems in the world, increasing the risk of other chronic diseases. Alterations in fatty acid synthesis related genes are crucially involved in obesity progression. Diosgenin (DG) was one of the phytosterols compounds with vital activity against lipid disorders. Therefore, this study was intended to evaluate the protective effect of DG on lipogenesis in the high-fat diet (HFD)-induced obesity in mice, via investigating the expression of two of the fatty acid synthesis–involved genes; sterol regulatory element-binding protein (SREBP-1c) and fatty acid synthase (FASN) genes. Thirty adult male mice were divided into 3 groups. Control group, fed with normal diet; HFD group, mice fed with a high-fat diet and HFD + DG group, mice fed with a high-fat diet and supplemented in parallel with DG for 6 consecutive weeks. The effect of DG on Body weights, liver enzymes, lipid profile, were evaluated. Histopathological fatty changes as well as SREBP-1c and FASN gene expression were also investigated. DG significantly alleviated body weight gain, adjusted liver enzymes, and improved lipid profile. Additionally, DG ameliorated the histopathological changes by reducing the lipid vacuoles and hence the hepatosteatosis. Accordingly, DG significantly downregulated the two-fold increase in the SREBP-1c and FASN gene expression observed in the HFD group. In conclusion, DG possesses a beneficial impact against diet-induced obesity in mice, which makes it a good candidate for NAFLD and obesity prevention.

A circRNA-miRNA-mRNA network plays a role in the protective effect of diosgenin on alveolar bone loss in ovariectomized rats

BackgroundThe present study aimed to assess the perturbation in circular RNA (circRNA)/mRNA expression profiles and a circRNA-miRNA-mRNA coexpression network involved in the potential protective effect of diosgenin (DIO) on alveolar bone loss in rats subjected to ovariectomy (OVX).MethodsThe Wistar rats (female) manipulated with sham operation were classified as the SHAM group and the grouping of OVX rats administered with DIO, estradiol valerate or vehicle for 12 weeks was DIO group, EV group and OVX group respectively. Following treatments, the plasmatic levels of osteocalcin and tumor necrosis factor-alpha and the microstructure of alveolar bone were assayed. Based on microarray analyses, we identified differentially expressed (DE) circRNAs and mRNAs in alveolar bone of rats in both OVX and DIO group. The DE circRNAs and DE mRNAs involved in the bone metabolism pathway validated by RT-qPCR were considered key circRNAs/mRNAs. On the basis of these key circRNAs/mRNAs, we predicted the overlapping relative miRNAs of key circRNAs/mRNAs, and a circRNA-miRNA-mRNA network was built.ResultsDIO showed an anti-osteopenic effect on the rat alveolar bone loss induced by OVX. In total, we found 10 DE circRNAs (6 downregulated and 4 upregulated) and 614 DE mRNAs (314 downregulated and 300 upregulated) in samples of the DIO group compared with those of the OVX group. However, only one circRNA (rno_circRNA_016717) and seven mRNAs (Sfrp1, Csf1, Il1rl1, Nfatc4, Tnfrsf1a, Pik3c2g, and Wnt9b) were validated by qRT-PCR and therefore considered key circRNA/mRNAs. According to these key circRNA/mRNAs and overlapping predicted miRNAs, a coexpression network was constructed. After network analysis, one circRNA-miRNA-mRNA axis (circRNA_016717/miR-501-5p/Sfrp1) was identified.ConclusionThe mechanism of DIO inhibiting alveolar bone loss after OVX is possibly relevant to the simultaneous inhibition of osteogenesis and osteoclastogenesis by mediating the expression of important molecules in the Wnt, PI3K, RANK/RANKL or osteoclastogenic cytokine pathways. The circRNA_016717/miR-501-5p/Sfrp1 axis may play important roles in these processes.

Protective effect of diosgenin on LPS/D-Gal-induced acute liver failure in C57BL/6 mice

Acute liver failure (ALF) is a deadly clinical syndrome, which leads to a rapid loss of normal liver function. Diosgenin is a natural steroidal sapogenin found in various plant families. Various studies have shown that diosgenin have therapeutic or preventive effect in various diseases such as cancer, cardiovascular disorders, type 2 diabetes, and neurodegenerative disorders. In this study, we evaluated effects of diosgenin on mice model of ALF. Animal model of ALF was induced by intraperitoneal injection of lipopolysaccharide (LPS)/d-galactosamine (D-Gal). The male C57BL/6 mice were randomly divided into 3 groups: control group, LPS/D-Gal group, and LPS/D-Gal + diosgenin group (50 mg/kg). Mice in the LPS/D-Gal group received a combination of LPS (50 μg/kg) and D-Gal (400 mg/kg) intraperitoneally. LPS/D-Gal + diosgenin group received diosgenin twice orally 24 h and 1 h before receiving LPS/D-Gal. Markers of liver injury including ALT, AST and ALP were measured in blood samples in addition to determination of oxidative stress and inflammatory markers including MDA, nitrite, ROS, catalase, SOD, Nrf2, IL-1β, IL-6, TLR4, TNF-α and NF-κB in hepatic tissue. Administration of diosgenin could greatly reduce serum levels of ALT, AST, and ALP. Besides, hepatic levels of MDA, ROS, IL-1β, IL-6, TLR4, TNF-α, and NF-κB significantly decreased and SOD activity and Nrf2 level increased in comparison with the LPS/D-Gal group. In addition, myeloperoxidase activity as a marker of neutrophil infiltration decreased following diosgenin administration. In summary, diosgenin led to reduction of liver injury indices and oxidative stress and inflammatory events and diosgenin has probably hepatoprotecive effects in ALF.

Effect of Diosgenin on the Circulating MicroRNA Profile of Ovariectomized Rats.

The present study aimed to assess the changes in circulating microRNA (miRNA) expression profiles associated with the potential osteoprotective effect of diosgenin (DIO) in ovariectomized (OVX) rats. Wistar rats (female) were subjected to a sham operation (SHAM group) or ovariectomy. OVX rats were treated with DIO (DIO group) or vehicle (OVX group) for 12 weeks. Following treatment, the serum estradiol, bone turnover biomarker levels, and the microarchitecture of tibias were assayed. Based on miRNA microarray and qRT-PCR analyses, differentially expressed (DE) circulating miRNAs were identified between the OVX and SHAM groups (comparison A) and between the DIO and OVX groups (comparison B). Furthermore, putative target genes of shared DE miRNAs with opposite expression trends in the two comparisons were predicted by ingenuity pathway analysis (IPA). Finally, the expression levels of the putative target genes in serum and tibia were validated by qRT-PCR. The micro-CT results demonstrated that DIO had a substantial anti-osteopenic effect on the tibias of OVX rats. In total, we found 5 DE circulating miRNAs (four upregulated and one downregulated) in comparison A and 21 DE circulating miRNAs (15 upregulated and 6 downregulated) in comparison B. However, only one DE circulating miRNA (rno-miR-20a-5p) had opposite expression trends between the two comparisons. Including rno-miR-20a-5p, 7 of the 10 selected DE circulating miRNAs between the two comparisons passed qRT-PCR validation. Specifically, based on qRT-PCR validation, DIO upregulated the expression of rno-miR-20a-5p and downregulated that of three target genes (Tnf, Creb1, and Tgfbr2) of the “osteoclast differentiation” pathway in the tibias of OVX rats. Our results suggested that DIO could change the circulating miRNA profile of OVX rats and inhibited the downregulation of miR-20a-5p in serum and tibia. DIO might exert an anti-osteoclastogenic effect on OVX rats by upregulating the expression of miR-20a-5p in circulation and bone tissue.

Effect of diosgenin on T-helper 17 cells in mice with collagen-induced arthritis

Background: Diosgenin, obtained from Dioscorea nipponica Makino, possesses anti-inflammatory properties. Objective: The objective of this study is to explore the therapeutic effects of diosgenin against collagen-induced arthritis (CIA) in DBA/1J mice. Materials and Methods: The CIA model was established using chicken type II collagen-immunized DBA1/J mice (0.1 mL/mouse), with the same stimulus repeated on day 21. Next, the CIA mouse model was selected, and inguinal lymph nodes were excised to obtain a single-cell suspension. Using CCK-8, control group, model group, and high-/medium-/low-dose diosgenin group were set based on drug toxicity. Next, the ratio of T-helper 17 cells (Th17) to CD3+ T cells was analyzed using flow cytometer. The levels of interleukin 17 (IL)-17 and IL-6 were determined by the enzyme-linked immunosorbent assay. The expression of RORγt was determined using the reverse-transcription quantitative real-time polymerase chain reaction and Western blot analysis. Results: An in vitro inhibitory rate of ≥ 70% was set as the cutoff value to select the high (25 μmol/L), medium (12.5 μmol/L), and low (6.25 μmol/L) doses of diosgenin. The Th17 cell ratio in CD3+ T cells, the levels of IL-17 and IL-6, and mRNA and protein expression of RORγt showed significantly increased tendency in the model group compared with the control group (P

Diosgenin and Its Fenugreek Based Biological Matrix Affect Insulin Resistance and Anabolic Hormones in a Rat Based Insulin Resistance Model.

Fenugreek is known since ancient times as a traditional herbal medicine of its multiple beneficial effects. Fenugreek's most studied and employed effect is its hypoglycemic property, but it can also be useful for the treatment of certain thyroid disorders or for the treatment of anorexia. The regulation of glucose homeostasis is a complex mechanism, dependent on the interaction of different types of hormones and neurotransmitters or other compounds. For the study of how diosgenin and fenugreek seeds modify insulin sensitivity, we used a rat insulin resistance model induced by high-fat diet. Diosgenin in three different doses (1mg/bwkg, 10mg/bwkg, and 50 mg/bwkg, respectively) and fenugreek seed (0.2 g/bwkg) were administered orally for 6 weeks. Insulin sensitivity was determined by hyperinsulinemic euglycemic glucose clamp method. Our research group found that although glucose infusion rate was not significantly modified in either group, the increased insulin sensitivity index and high metabolic clearance rate of insulin found in the 1 mg/kg diosgenin and the fenugreek seed treated group suggested an improved peripheral insulin sensitivity. Results from the 10 mg/kg diosgenin group, however, suggest a marked insulin resistance. Fenugreek seed therapy results on the investigated anabolic hormones support the theory that, besides insulin and gastrointestinal peptides, the hypothalamic-hypopituitary axis regulated hormones synchronized action with IGF-1 also play an important role in the maintaining of normal glucose levels. Both diosgenin and fenugreek seeds are capable of interacting with substrates of the above-mentioned regulatory mechanisms, inducing serious hormonal disorders. Moreover, fenugreek seeds showed the ability to reduce the thyroid hormone levels at the periphery and to modify the T4/T3 ratio. It means that in healthy people this effect could be considered a severe side effect; however, in hypothyroidism this effect represents a possibility of alternative natural therapy.

Effects of Sanyaku and Its Constituent Diosgenin on the Fasted and Postprandial Hypertriacylglycerolemia in High-Fat-Diet-Fed KK- A y Mice.

In this study, we examined the fasted and postprandial triacylglycerol (TG) levels in KK- A y mice fed a high-fat diet (HFD) or a HFD containing either 500 ppm (0.05%) of diosgenin or 500 ppm (0.05%) of diosgenin-containing Chinese yam sanyaku. Oral fat tolerance tests revealed that, not only in the fasting state but also after loading of lipid emulsion, plasma levels of TG were significantly reduced in sanyaku- and diosgenin- fed mice. Levels of fat oxidation, especially in the dark phase (from 7 p.m. to 7 a.m.), were increased in the sanyaku and diosgenin groups. Moreover mRNA levels of lipoprotein lipase and peroxisome proliferator-activated receptor γ, coactivator 1α were moderately upregulated in the liver of sanyaku- and diosgenin-ingested mice. These results suggest that consecutive ingestion of diosgenin or diosgenin-containing sanyaku at the dose achievable in a human diet potentially ameliorates fasted and postprandial hypertriacylglycerolemia, which could be associated with the improvement of TG metabolism.

Diosgenin protects against alveolar bone loss in ovariectomized rats via regulating long non-coding RNAs.

The present study assessed the changes in long non-coding (lnc)RNA and mRNA expression profiles when diosgenin (DIO) exerted a potential osteoprotective effect on the alveolar bone of ovariectomized (OVX) rats. Female Wistar rats underwent a sham operation (SHAM group) or ovariectomy. OVX rats were treated using vehicle (OVX group), DIO (DIO group) or estradiol valerate (EV group) for 12 weeks. After treatment, the biomarkers of bone turnover in plasma and the microstructure of alveolar bone were assessed. lncRNA microarrays were applied to assess lncRNA and mRNA expression profiles in alveolar bone in the OVX and DIO group rats. Subsequently, the differentially expressed mRNAs associated with the comprehensive bone metabolism pathway in Ingenuity Pathway Analysis (IPA) were identified and regarded as key mRNAs. Based on some of the key mRNAs and all the differentially expressed lncRNAs, a coexpression network was established and this network was further analyzed to identify the top 6 lncRNAs with the highest closeness scores (pivotal lncRNAs). Finally, 6 modules showing interactions between pivotal lncRNAs and key mRNAs were constructed. All of the pivotal lncRNAs and key mRNAs were validated with reverse transcription-quantitative polymerase chain reaction. The present findings demonstrated that DIO suppressed the loss of alveolar bone in OVX rats, and the changes to the expression of some lncRNAs or mRNAs occurred in the alveolar bone of the rats in the DIO group. Twenty-four key mRNAs were identified during pathway analysis. Furthermore, 8/24 key mRNAs (Ctnnb1, Smad4, Tcf2, Sp7, Il1b, Il1r1, Tnf and Tnfrsf1a) were used to establish a coexpression network, which included 1,656 nodes and 5,341 edges. During network analysis, 6 pivotal lncRNAs (XR_008346, MRuc007iji, MRAK157089, MRAK076413, MRAK143591 and AB036696) were obtained, and 6 modules illustrating pivotal lncRNA-key mRNA interactions were identified. These results revealed that the anti-osteoporotic effect of DIO on alveolar bone may be associated with the promotion of a bone formation process through increasing the signaling of the Wnt and BMPs pathways and the inhibition of the bone resorption process through decreasing stimulators of osteoclastogenesis. To conclude, several pivotal lncRNAs may serve important roles in these processes via regulating some key mRNAs in the bone metabolism pathway.

Inhibitory effect of diosgenin on experimentally induced benign prostatic hyperplasia in rats.

This study investigated the effect of diosgenin, a natural sapogenin possessing various pharmacological activities, on benign prostatic hyperplasia (BPH) in rats and the possible mechanisms. BPH was established in the castrated rats by subcutaneous injection of testosterone propionate. Animals were randomly divided into four groups (n=10 each): model group (0.5% sodium carboxymethyl cellulose); positive control group (3 mg/kg finasteride); two diosgenin groups (50 and 100 mg/kg). The drugs were intragastricaly given in each group for consecutive 3 weeks. Another 10 rats with no testicles cut off served as negative controls and they were subcutaneously injected with 0.1 mL olive oil per day and then treated with 0.5% sodium carboxymethylcellulose. After 3-week administration, the prostate index and serum PSA level were determined, and histopathological examination was carried out. The levels of MDA, SOD and GPx in prostates were also measured. Additionally, the expression of Bcl-2, Bax and p53 was examined using Western blotting. The results showed that the prostate index and serum PSA level were significantly decreased, and the pathological changes of the prostate gland were greatly improved in diosgenin groups as compared with the model group. Elevated activities of SOD and GPx, and reduced MDA level were also observed in diosgenin-treated rats. In addition, the expression of Bcl-2 in prostates was down-regulated, whereas that of Bax and p53 was up-regulated in diosgenin-treated rats. These results indicated that diosgenin was effective in inhibiting testosterone propionate-induced prostate enlargement and may be a candidate agent for the treatment of BPH.

Diosgenin prevents bone loss on retinoic acid-induced osteoporosis in rats.

To observe the preventive and therapeutic effects of diosgenin on retinoic acid-induced osteoporosis in rats. A total 50 Sprague-Dawley rats were randomly divided into 5 groups: control group, model group (osteoporosis rats), low (10mgkg(-1)), middle (30mgkg(-1)), and high-dose diosgenin (90mgkg(-1))-treated groups. The osteoporosis rats model was induced by retinoic acid. The BMD and physical parameters of femoral including length, wet weight, and dry weight in each group were measured. The hematoxylin-eosin staining was used for bone histomorphology analysis. Besides, the bone calcium (Ca) and phosphorus (P) contents were measured. In order to detect the biochemical index in different treatment groups, the serum tartrate-resistant acid phosphatase (TRAP), alkaline phosphatase (ALP), estradiol, and osteocalcin were compared among different groups. The osteoporosis rat model was successfully induced by retinoic acid. Compared with the model group, the lessening of femoral length and weight and the loss of BMD were significantly improved in diosgenin groups. Both contents of Ca and P were much more increased when induced by retinoic acid (p<0.05). The estradiol and osteocalcin levels in the middle and high-dose treatment groups were significantly higher than that of the model group, while the ALP and TRAP levels were much lower than the model group (p<0.05). Diosgenin can prevent the loss of bone in experimental rats. The mechanism may be that it improves the level of estrogenic hormone of estradiol and inhibits the high bone turnover.

Antioxidative and Hypolipidemic Effects of Diosgenin, a Steroidal Saponin of Yam (Dioscorea spp.), on High-Cholesterol Fed Rats

Diosgenin (a steroidal saponin of yam) has long been used as a raw material for the industrial production of steroid drugs, and reported to have a hypocholesterolemic effect by suppressing cholesterol absorption and increasing cholesterol secretion. Oxidative stress has been suggested as a main risk factor in the development of atherosclerosis. The aim of this study is to investigate the possible hypolipidemic and antioxidative effect of diosgenin on rats fed with a high-cholesterol diet supplemented with either 0.1% or 0.5% diosgenin for 6 weeks. We measured the lipid profile in the plasma and liver, lipid peroxidation and antioxidative enzyme activities in the plasma, erythrocyte and gene expression of antioxidative enzymes in the liver, and the oxidative DNA damage in lymphocytes. Diosgenin showed a decrease in the plasma and hepatic total cholesterol levels, but increased the plasma high-density lipoprotein (HDL) cholesterol level. Erythrocyte TBARS and lymphocyte DNA damage measured by the comet assay were decreased in the diosgenin supplemented group. Furthermore, diosgenin feeding enhanced the resistance to lymphocyte DNA damage caused by an oxidant challenge with H(2)O(2). The antioxidative enzyme activities were also affected by diosgenin supplementation. Total superoxide dismutase (SOD) in the plasma and liver, glutathione peroxidase (GSH-Px) in erythrocytes, and catalase (CAT) in erythrocytes and liver were significantly increased in the 0.5% diosgenin group. The expression of antioxidative enzymes was up-regulated by diosgenin, the expression of GSH-Px being the highest in the 0.5% diosgenin group. These results suggest that diosgenin could be a very useful compound to control hypercholesterolemia by both improving the lipid profile and modulating oxidative stress.

Alteration of the expression of adenosine triphosphate‐binding cassette transporters associated with bile acid and cholesterol transport in the rat liver and intestine during cholestasis

Multidrug resistance protein 2 (Mrp2), Mrp3, adenosine triphosphate-binding cassette transporter g5 (Abcg5) and adenosine triphosphate-binding cassette transporter g8 (Abcg8) have been identified as bile acid or cholesterol transporter in the enterocytes as well as hepatocytes. The purpose of the present study was to evaluate intestinal and hepatic adenosine triphosphate-binding cassette transporter expressions during cholestasis. Experiment 1: Rats were subjected to bile duct ligation or sham operation. Blood, liver and small intestines were obtained 24 and 72 h after operation. Experiment 2: Rats were divided into four groups as follows: (i) control group; (ii) diosgenin group (fed with diosgenin in diet [1%(wt/wt)] for 7 days); (iii) ethinyl estradiol group (received ethinyl estradiol [5 mg/kg daily] for 5 days); and (iv) diosgenin-ethinyl estradiol group (received ethinyl estradiol and diosgenin). After treatment, blood, bile, liver and intestines were obtained. The mRNA related to lipid and bile acid metabolism was analyzed by reverse transcription polymerase chain reaction. Intestinal Mrp2 and Abcg5/Abcg8 mRNA expression remarkably decreased 24 h after bile duct ligation (43% and 61%/54% of sham operation) and recovered 72 h after bile duct ligation (103% and 95%/83% of sham operation). Intestinal Mrp3 mRNA expression did not change after bile duct ligation. Intestinal Mrp2 mRNA expression was remarkably increased in diosgenin and diosgenin-ethinyl estradiol groups in comparison with the control group. There were no significant differences in intestinal Mrp3 mRNA expression among the four groups. Hepatic Mrp3 mRNA expression was remarkably increased in the D, EE and DE groups in comparison with the control group (531%, 321% and 1160% of control, respectively, P < 0.01). Hepatic Abcg5 and Abcg8 mRNA expression decreased in ethinyl estradiol and diosgenin-ethinyl estradiol groups compared with the control group and there were no differences in intestinal Abcg5 and Abcg8 mRNA expressions among the four groups. Bile duct ligation affects not only hepatic but also the intestinal Mrp2 and Abcg5 and Abcg8 expressions. Intestinal Mrp2 mRNA level was regulated by factor in the lumen (e.g. diosgenin feeding). Cholestasis by ethinyl estradiol treatment was enhanced by diosgenin and the increase in hepatic Mrp3 mRNA level might affect the enhancement.

Regulation of biliary cholesterol secretion is associated with abcg5 and abcg8 expressions in the rats: effects of diosgenin and ethinyl estradiol

In this study, we evaluate the effect of diosgenin, ethinyl estradiol and these co-administration on changes of lipoprotein metabolism and expression of hepatic genes those are important for cholesterol metabolism including the recently identified abcg5 and abcg8 in male Wistar rats. Rats were subjected to four experimental groups: (1) control group, (2) diosgenin group, which was fed the diet containing 1% diosgenin for 7 days, (3) ethinyl estradiol group, which received ethinyl estradiol in a dose of 5 mg/kg daily for 5 days, (4) diosgenin–ethinyl estradiol group, which received ethinyl estradiol treatment and was fed the diet containing 1% diosgenin. Diosgenin-feeding induced the hepatic abcg5/ abcg8 expressions and biliary cholesterol secretion. Ethinyl estradiol administration reduced hepatic abcg5/ abcg8 expressions and biliary cholesterol secretion. There was a positive correlation between hepatic expressions of abcg5/abcg8 and biliary cholesterol secretion. These findings strongly suggest that abcg5 and abcg8 are key proteins for biliary cholesterol excretion. Diosgenin-feeding did not affect the hepatic abcg5/ abcg8 expressions and biliary cholesterol excretion in ethinyl estradiol-treated rat. Serum bile acid and bilirubin were higher and biliary bile acid and bilirubin secretions were lower in diosgenin–ethinyl estradiol group than those in ethinyl estradiol group. This finding suggests that diosgenin enhances the cholestatic effect of ethinyl estradiol in the rat. In conclusion, alteration of biliary cholesterol secretion is related to the expressions of hepatic abcg5 and abcg8 in diosgenin- or ethinyl estradiol-treated rat.

Low temperature crystal structure of natural diosgenone.

The molecular structure of diosgenone, a natural steroidal sapogenin, closely related to diosgenin and isolated from Solanum nudum, was solved by single crystal X-ray diffractometry at 120 K and refined by full-matrix least-squares to an agreement factor, R1 = 0.054. It crystallizes in the monoclinic space group P2(1), with a = 15.1870(4) A, b = 7.2710(2) A, c = 21.2840(6) A, beta = 99.251(1) degrees, and four molecules in the unit cell (Z = 4). The results constitute the first structural report on a steroidal sapogenin from the diosgenin group.