The regulation of alfalfa saponin extract on key genes involved in hepatic cholesterol metabolism in hyperlipidemic rats

Non-Thermal Plasma (NTP) Treatment of Alfalfa Seeds in Different Voltage Conditions Leads to Both Positive and Inhibitory Outcomes Related to Sprout Growth and Nutraceutical Properties

Non-thermal plasma (NTP) has proven to be a green method in the agricultural field for the stimulation of germination, growth, and production of nutraceutical compounds in some cases. However, the process is far from being fully understood and depends on the targeted plant species and the NTP used. In this work, we focus on the production of alfalfa sprouts from NTP-treated seeds under different voltage conditions. A flexible electrode configuration was used to produce the NTP, which can also be placed on packages for in-package treatments. The surface of the seeds was analyzed, indicating that the microstructure was strongly affected by NTP treatment. Biometric measurements evidenced the possibility of stimulating the sprout growth in some conditions by up to 50% compared to the sprouts obtained from untreated seeds. Biochemical traits for the sprouts obtained in different processing conditions were also studied, such as the concentrations of chlorophyll pigments, flavonoids and polyphenols, and antioxidant activity. Most NTP treatments led to inhibitory effects, proving the strong dependence between NTP treatment and targeted plant species.

Alfalfa Xeno-miR168b Target CPT1A to Regulate Milk Fat Synthesis in Bovine Mammary Epithelial Cells

It was shown that microRNAs (miRNAs) play an important role in the synthesis of milk fat; thus, this manuscript evaluated whether exogenous miRNA (xeno-miRNAs) from alfalfa could influence the milk fat content in dairy cows. At first, mtr-miR168b was screened from dairy cow milk and blood. Then, EdU staining, flow cytometry, Oil Red O staining, qRT-PCR, and WB were applied to explore the effect of xeno-miR168b on the proliferation, apoptosis, and lipid metabolism of bovine mammary epithelial cells (BMECs). Finally, in order to clarify the pathway that regulated the lipid metabolism of BMECs using xeno-miR168b, a double-luciferase reporter assay was used to verify the target gene related to milk fat. These results showed that overexpression of xeno-miR168b inhibited cell proliferation but promoted apoptosis, which also decreased the expression of several lipid metabolism genes, including PPARγ, SCD1, C/EBPβ, and SREBP1, significantly inhibited lipid droplet formation, and reduced triglyceride content in BMECs. Furthermore, the targeting relationship between CPT1A and xeno-miR168b was determined and it was confirmed that CPT1A silencing reduced the expression of lipid metabolism genes and inhibited fat accumulation in BMECs. These findings identified xeno-miR168b from alfalfa as a cross-kingdom regulatory element that could influence milk fat content in dairy cows by modulating CPT1A expression.

Alfalfa saponins inhibit oxidative stress-induced cell apoptosis through the MAPK signaling pathway

BACKGROUND

Oxidative stress could seriously affect the growth performance of piglets. As natural extracts of Alfalfa (Medicago sativa), alfalfa saponins have been shown to function as antioxidants in piglets in vivo. However, few studies have investigated the effects and mechanism of alfalfa saponins against oxidative stress in piglet cells in vitro. In the current study, piglets' small intestinal epithelial cell line (IPEC-J2) was explored to investigate the protective effects of alfalfa saponins on injured cells induced by H2O2.

METHODS

To investigate the effects and mechanism of alfalfa saponins against oxidative stress in piglet cells, the cell viability, activity of antioxidant enzymes, LDH and the amount of MDA were detected in H2O2-treated cells after the cells were pre-incubated with alfalfa saponins. The mechanism of alfalfa saponins against H2O2-induced oxidative cell damage was explored by detecting the expression of mitochondrial apoptosis-related proteins. Furthermore, the signaling pathway of alfalfa saponins in IPEC-J2 cells under oxidative stress was also investigated.

RESULTS

The results indicated that alfalfa saponins could rescue cell viability, elevate the activity of antioxidant enzymes and down-regulate the activity of LDH and the amount of MDA in H2O2-induced cells.

CONCLUSION

Alfalfa saponins could inhibit oxidative stress-induced cell mitochondrial apoptosis through the MAPK signaling pathway, thereby providing a new method for improving antioxidant stress ability by means of nutritional regulation.

Effects of alfalfa saponins on the production performance, serum biochemical factors, and immune factors in Small-Tailed Han sheep

This study aimed to determine the potential effects of alfalfa saponins on the production performance, serum biochemical factors, and immune factors in sheep. Twenty Small-Tailed Han sheep were equally and randomly divided into Groups 1–4, fed with diets containing 0, 5, 10, and 20 g alfalfa saponins per kg, respectively, for 40 consecutive days. During the treatments, the body weight change was recorded for each sheep. Before, during, and after the treatments of alfalfa saponins, serum was collected from each group to compare the levels of biochemical and immune factors. All sheep were killed after the treatments, and the longissimus dorsi muscle was collected to compare the meat quality. The results validated the effects of alfalfa saponins on the growth performance and meat quality in Small-Tailed Han sheep, and the supplementation level of 10 g/kg was the best. Alfalfa saponins also had effects on the levels of biochemical factors in serum. However, both dose- and time-dependent effects were observed. After a shorter feeding period (14 days), the concentrations of cholesterol (CHOL) and low-density lipoprotein (LDL) in Groups 2, 3, and 4 were all lower than those in the control group; however, when alfalfa saponins were continuously fed, this effect was not apparent or even gone. Supplying alfalfa saponins increased serum concentrations of IgA, IgG, IgE, IgM, IL-1, IFN-α, and IFN-β. And this effect was distinctly observed in Groups 3 and 4. Based on the current results, the alfalfa saponins concentration of 10 g/kg (for 14 consecutive days) could be suggested as the optimum ratio for good health conditions of Small-Tailed Han sheep.

The Antioxidant Properties of Alfalfa (Medicago sativa L.) and Its Biochemical, Antioxidant, Anti-Inflammatory, and Pathological Effects on Nicotine-Induced Oxidative Stress in the Rat Liver

Medicago sativa Linn or alfalfa is a tonic plant rich in proteins, vitamins, and minerals that is used to treat many diseases due to its pharmacological properties such as anti-inflammatory and antioxidant activities. So, the aim of this study was to evaluate the efficacy of alfalfa methanolic extract (AME) on the prevention of liver damage caused by nicotine. The total phenols, flavonoids levels, and the free radical scavenging activity of its extract (IC50) were measured. In this study, 30 Wistar rats were randomly divided into 5 groups as control (untreated), N (nicotine only), T1, T2, and T3 (nicotine + AME 100, 250, and 500 mg/kg/day, respectively). AME (orally) and nicotine (intraperitoneal injection, 0.5 mg/kg/day) were then administered for 21 days. Weight gain, the liver-to-body weight ratio, liver functional enzymes, and the lipid profile were measured. Moreover, we evaluated oxidative stress, proinflammatory parameters, and histopathological changes in the liver. Total phenols, flavonoids, and IC50 were determined as $51.68\pm 0.62$  mg GAE/g, $18.55\pm 1.01$  mg QE/g, and $350.91\pm 16.46$  μg/ml, respectively. Nicotine changed the measured parameters to abnormal. AME increased weight gain, the liver-to-body weight ratio, and enzymatic antioxidant levels and decreased malondialdehyde, liver functional enzymes, and proinflammatory cytokine levels. The lipid profile and histopathological changes have also been improved by AME in a dose-dependent manner. The results showed that AME in a dose-dependent manner by improving the inflammation and oxidative damage could improve the liver damage caused by nicotine.

Ipomea batatas Leaf Powder from Cameroon: Antioxidant Activity and Antihyperlipidemic Effect in Rats Fed with a High-Fat Diet

The present study consists of analyzing the phytochemical composition of Ipomoea batatas leaf powders and evaluating their antihyperlipidemic effect on rats receiving a high-fat diet. Ipomoea batatas leaves were collected from four agroecological areas of Cameroon, and powders were obtained after washing, drying, grinding, and sieving. Standard analytical methods were used to determine the phytochemical composition of two varieties (IRAD-tib1yellow-V1 and IRAD-1112white-V2) from North Z1, Adamawa Z2, West Z3, Center Z4. The effect of I. batatas leaf powder on lipid metabolism was assessed in vivo by feeding different groups of rats with a high-fat diet supplemented with 5 and 10% of I. batatas leaf powder during 30 days. At the end of the experimentation, total cholesterols, triglycerides, LDL- (low-density lipoprotein-) cholesterol, HDL- (High-density lipoprotein-) cholesterol, ASAT (aspartate aminotransferase), ALAT (alanine aminotransferase), and creatinine were measured using commercial enzymatic kits (Spinreact, Spain). The results of phytochemical analysis of I. batatas leaf powders revealed that the total phenol content ranged from 660.173 mg GAE/100 gDW (Z1V2) to 657.76 mg GAE/100 gDW (Z3V2), the flavonoids content ranged from 282.25 mgEC/100 gDW (Z3V1) to 325.05 mgEC/100 gDW (Z4V2), and the anthraquinone content ranged from 324.05 mg/100 gDW (Z3V2) to 326.72 mg/100 gDW (Z4V2). The total antioxidant capacity ranged from 19.00 (Z1V1) to 23.48 mg AAE/gDW (Z3V2), while the IC₅₀ ranged from 1.58 mg/mL (Z1V1) to 3.08 mg/mL (Z3V2). Rats fed a high-fat diet and supplemented with 5 and 10% of I. batatas leaf powder showed a significant (p < 0.05) reduction in body weight compared to the control with a reduction rate ranging from 6 to 10%. The consumption of I. batatas leaf powder for 30 days significantly (p < 0.05) reduced serum total cholesterol, LDL-cholesterol, triglycerides, ALAT, and creatinine level. These results suggest the use of I. batatas leaves as a phytomedicine in the treatment of cardiovascular diseases.

Isolation and identification of a flavonoid compound and in vivo lipid-lowering properties of Imperata cylindrica

Cogon grass (Imperata cylindrica/I. cylindrica) of the Gramineae family is found abundantly in nature, and the roots of this plant possess several beneficial biological properties. The present study aimed to isolate and identify flavonoid compounds from cogon grass roots and examine their potential as hypocholesterolemic agents. The flavonoid compound was isolated using a maceration method, followed by gravity column chromatography until a pure compound was obtained. The molecular structure of the isolated compound was determined using 1H-nuclear magnetic resonance (NMR) and 13C-NMR spectroscopy. An in vivo lipid-lowering test used a randomized post-test only control group experimental design in rats with hypercholesterolemia. The animals were divided into four groups: K0, negative control; K1, positive control; K2, ethanol extract treated group; and K3, ethyl acetate fraction treated group, and the lipid profiles were examined at the end of the study. The isolated compound, 7,3',5'-trimethoxyflavonol, was collected in yellow powder form; was shown to be a flavonoids and was comprised of 18 carbon atoms and 16 hydrogen atoms. In vivo tests demonstrated that 15 mg/200 g body weight (BW) of an ethanol extract significantly lowered total cholesterol levels (P=0.001) but did not lower low-density lipoprotein (LDL) (P=0.109) and high-density lipoprotein (HDL) levels (P=0.003). The fraction of ethyl acetate administered at 15 mg/200 g BW was capable of lowering the total cholesterol levels significantly (P=0.002) and lowered LDL levels (P=0.006) but was unable to increase HDL levels (P=0.190). The in vivo tests showed that the ethyl acetate fraction of I. cylindrica reduced total cholesterol and LDL levels more effectively than the ethanol extract, but did not affect HDL levels in rats with hypercholesterolemia.

Comparative Study of the Bioactive Properties and Elemental Composition of Red Clover (Trifolium pratense) and Alfalfa (Medicago sativa) Sprouts during Germination

Considering the growing interest in functional foods, the identification of the individual species of elements is of great importance in understanding specific nutraceutical properties. The present study aims to compare the dynamic of the elemental content (K, Na, Ca, Mg, Fe, Cu, Zn, Mn, Ni, and Se), total polyphenols, and antioxidant activity of Trifolium pratense L. and Medicago sativa L. sprouts in different germination stages. The elemental profile was established by atomic absorption spectroscopy after the microwave acid digestion of the samples, while total polyphenols and anti-radical activity were evaluated by UV-Vis spectroscopic methods. Phenolic compounds and anti-radical activity of both alfalfa and red clover sprouts varied with germination stages. Germination can significantly increase the anti-radical activity in the first 3 days of germination, followed by a decline in the following days. An increase in total polyphenols was noticed, starting from the second day of germination in both plant species. There were significant (p < 0.05) differences for Ca, Na, Fe, K, Zn, and Mg contents among the sprouts, depending on the germination stage and plant species. The calcium contents of alfalfa ranged between 200.74 µg/g DW (raw seeds) and 2765.31 µg/g DW (sprouted), while in red clover between 250.83 µg/g DW and 601.59 µg/g DW. Maximum selenium content in alfalfa sprouts, reached in the 3rd day of germination (11.42 µg/g DW), exceeded the maximum value measured in red clover (9.42 µg/g DW). The data were subject to statistical processing using analysis of variance (ANOVA), multivariate analysis (PCA) and hierarchical clustering analysis (HCA).

The Effects of Domestication on Secondary Metabolite Composition in Legumes

Legumes are rich in secondary metabolites, such as polyphenols, alkaloids, and saponins, which are important defense compounds to protect the plant against herbivores and pathogens, and act as signaling molecules between the plant and its biotic environment. Legume-sourced secondary metabolites are well known for their potential benefits to human health as pharmaceuticals and nutraceuticals. During domestication, the color, smell, and taste of crop plants have been the focus of artificial selection by breeders. Since these agronomic traits are regulated by secondary metabolites, the basis behind the genomic evolution was the selection of the secondary metabolite composition. In this review, we will discuss the classification, occurrence, and health benefits of secondary metabolites in legumes. The differences in their profiles between wild legumes and their cultivated counterparts will be investigated to trace the possible effects of domestication on secondary metabolite compositions, and the advantages and drawbacks of such modifications. The changes in secondary metabolite contents will also be discussed at the genetic level to examine the genes responsible for determining the secondary metabolite composition that might have been lost due to domestication. Understanding these genes would enable breeding programs and metabolic engineering to produce legume varieties with favorable secondary metabolite profiles for facilitating adaptations to a changing climate, promoting beneficial interactions with biotic factors, and enhancing health-beneficial secondary metabolite contents for human consumption.

Pinto Beans (Phaseolus vulgaris L.) Lower Non-HDL Cholesterol in Hamsters Fed a Diet Rich in Saturated Fat and Act on Genes Involved in Cholesterol Homeostasis

BACKGROUND

Pinto beans contain multiple active agents such as polyphenols, flavonoids, and saponins, and have been shown to lower cholesterol, but the mechanisms involved in this effect have not been explored.

OBJECTIVE

This study was to investigate the changes in cholesterol metabolism in response to whole pinto beans (wPB) and their hulls (hPB) supplemented into a diet rich in saturated fat and the molecular mechanisms potentially responsible for these effects in hamsters.

METHODS

Forty-four 9-wk-old male Golden Syrian hamsters were randomly assigned to 4 diet groups (n = 11), including a 5% (wt:wt) fat diet [normal-fat diet (NF)], a 15% (wt:wt) fat diet [diet rich in saturated fat (HSF), saturated fatty acids accounted for 70% of total fatty acids], or HSF supplemented with 5% (wt:wt) wPB or 0.5% (wt:wt) hPB for 4 wk. Plasma, liver, intestinal, and fecal samples were collected to evaluate multiple cholesterol markers and gene targets.

RESULTS

The plasma non-high-density lipoprotein (non-HDL) concentration was significantly reduced in the wPB- and hPB-supplemented groups by 31.9 ± 3.5% and 53.6 ± 3.2%, respectively, compared with the HSF group (P < 0.01), to concentrations comparable with the NF group. The wPB-supplemented hamsters had significantly lower liver cholesterol (45.1%, P < 0.001) and higher fecal cholesterol concentrations (94.8%, P = 0.001) than those fed the HSF. The expressions of hepatic 3-hydroxy-3-methylglutaryl CoA reductase (Hmgcr) and small intestinal acyl-coenzyme A: cholesterol acyltransferase 2 (Acat2) were significantly decreased in animals administered wPB (by 89.1% and 63.8%, respectively) and hPB (by 72.9% and 47.7%, respectively) compared with their HSF-fed counterparts (P < 0.05). The wPB normalized the expression of Acat2 to the level of the NF group.

CONCLUSION

Pinto beans remediated high cholesterol induced by HSF in male hamsters by decreasing hepatic cholesterol synthesis and intestinal cholesterol absorption, effects which were partially exerted by the hulls.

The effect of genistein on lipid levels and LDLR, LXRα and ABCG1 expression in postmenopausal women with hyperlipidemia

BACKGROUND

This study investigates the effect of genistein (Gen) on the lipid profiles and expression of low-density lipoprotein receptor (LDLR), liver X receptor α (LXRα) and ATP-binding cassette transporter G1 (ABCG1) in the plasma macrophages of postmenopausal women with hyperlipidemia in China.

METHODS

This study considered 187 cases, where 160 postmenopausal women had hyperlipidemia. The subjects were divided into placebo group (PG) and experimental group (EG). EG received 60 mg/day of Gen, PG received placebo for 6 months. Body weight, height, waist circumference, body mass index and glucose levels were determined according to standard operating procedures. The triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), apolipoprotein-A1 (Apo-A1) and apolipoprotein-B (Apo-B) levels were detected in the plasma macrophages using ELISA. The protein and mRNA expression levels of LDLR, LXRα and ABCG1 were detected by western blot and real-time PCR techniques, respectively.

RESULTS

Compared to the baseline, Gen effectively lowered TG, TC and LDL-C levels, whereas HDL-C levels as well as the protein and mRNA expression levels of LDLR, LXRα and ABCG1 (p < 0.05) were increased. There was a significant difference in the expression of LDLR protein between the two groups (p < 0.05). The mRNA expression levels of LDLR, LXRα and ABCG1 were significantly increased in the EG compared to the PG.

CONCLUSION

Gen effectively modulated the plasma lipid indices. The cholesterol-lowering effects of Gen may be attributed to its regulation on some of the key genes involved in cholesterol homeostasis.

Isolation and determination of saponin hydrolysis products from Medicago sativa using supercritical fluid extraction, solid-phase extraction and liquid chromatography with evaporative light scattering detection

Saponins are widespread secondary metabolites with various beneficial properties: fungicidal, antibacterial, antiviral, and anticancer. Alfalfa saponin molecules contain mainly: medicagenic acid, hederagenin, bayogenin, and soyasapogenol B. Structural diversity of saponins makes their determination in Medicago sativa extracts very difficult. The most popular determination technique is high-performance liquid chromatography applied with evaporative light scattering detection. Qualitative and quantitative analysis of sapogenins from Medicago sativa by high-performance liquid chromatography with evaporative light scattering detection required hydrolysis and purification of extracts obtained by supercritical fluid extraction. Hydrolysis of saponins with concentrated hydrochloric acid provided high concentration of medicagenic acid. In the purification process, satisfactory results were obtained for solid-phase extraction using octadecyl. Recoveries were from 71 to 99% with a standard deviation from 2 to 8. Hydrolysis with concentrated hydrochloric acid was the only method that allowed identification of all four analyzed sapogenins. Moreover, it is characterized by a short time of preparation, simplicity of execution, a small amount of the sample and solvents. The hydrolysis and purification methods coupled with high-performance liquid chromatography and evaporative light scattering detection can be successfully used for qualitative and quantitative analysis of the main saponins present in Medicago sativa plant extracts obtained by supercritical fluid extraction.

Effects of sanshoamides and capsaicinoids on plasma and liver lipid metabolism in hyperlipidemic rats

The objective of this study was to determine the effects of sanshoamides and capsaiciniods on plasma and liver lipid levels and the mRNA expression levels of key receptors involved in cholesterol metabolism in hyperlipidemic rats. A total of 56 three-week-old female Sprague-Dawley rats were assigned to 7 treatment groups based on initial body weight (n = 8 rats per group). With certain combinations of sanshoamides and capsaicinoids significantly increased food intake, reduced lipid levels in blood and liver, improved histological characteristics of a fatty liver, down regulated mRNA expression levels of cholesterol 7-alpha-hydroxylase (CYP7A1), 3-hydroxyl-3-methylglutary CoA (HMG-CoA) and Farnesoid X Receptor (FXR) in liver and apical sodium-dependent bile acid transporter, Ileal Bile Acid Binding Protein and FXR in the ileum in hyperlipidemic rats. These results indicated that dietary supplementation with sanshoamides and capsaicinoids reduced blood lipid levels and improved cholesterol metabolism in hyperlipidemic rats.

Dietary supplementation of defatted kenaf (Hibiscus cannabinus L.) seed meal and its phenolics-saponins rich extract effectively attenuates diet-induced hypercholesterolemia in rats

Kenaf is one of the important commercial fiber crops worldwide and defatted kenaf seed meal (DKSM) is a secondary by-product from the kenaf industry. Thus, efforts to turn this low-cost agricultural waste into value-added functional food ingredients will definitely bring advantageous impacts to the community health, environment and economy. The present study was aimed to investigate the cardioprotective properties of DKSM and its phenolics-saponins rich extract (PSRE) in diet-induced hypercholesterolemic rat model. Hypercholesterolemia was induced in Sprague-Dawley rats via atherogenic diet feeding and dietary interventions were conducted by incorporating DKSM (15% and 30%) and equivalent levels of PSRE (2.3% and 4.6%, respectively, equivalent to the total content of phenolics and saponins in DKSM groups) into the atherogenic diets. After 10 weeks of DKSM and PSRE supplementation, the hepatosomatic index, hepatosteatosis, serum lipid profile, Castelli risk indexes as well as hepatic and renal functions of hypercholesterolemic rats were significantly improved (p < 0.05). Besides, the levels of hepatic Hmgcr and serum Pcsk9 were lowered, along with transcriptional upregulations of hepatic Cyp7a1, Abca1, Lcat, ApoA2 and ApoE (p < 0.05). The gene expression of hepatic Ldlr was marginally enhanced by DKSM supplementation (p > 0.05), but superiorly upregulated by PSRE (p < 0.05). The combined results showed that hypercholesterolemia and the atherogenic risk in rats were effectively attenuated by DKSM and PSRE supplementation, possibly via modulations of multiple vital processes in hepatic cholesterol metabolism. Furthermore, phenolics and saponins may be the bioactives conferring DKSM and PSRE with their anti-hypercholesterolemic properties. In conclusion, DKSM and PSRE are prospective cardioprotective functional food ingredients for hypercholesterolemic individuals.

Therapeutic Potential of Temperate Forage Legumes: A Review

The discovery of bioactive molecules from botanical sources is an expanding field, preferentially oriented to plants having a tradition of use in medicine and providing high yields and availability. Temperate forage legumes are Fabaceae species that include worldwide-important crops. These plants possess therapeutic virtues that have not only been used in veterinary and folk medicine, but have also attracted the interest of official medicine. We have examined here Medicago sativa (alfalfa), Trifolium pratense and T. repens (clovers), Melilotus albus and M. officinalis (sweet clovers), Lotus corniculatus (birdsfoot trefoil), Onobrychis viciifolia (sainfoin), Lespedeza capitata (roundhead lespedeza), and Galega officinalis (goat's rue). The phytochemical complexes of these species contain secondary metabolites whose pharmacological potentials deserve investigation. Major classes of compounds include alkaloids and amines, cyanogenic glycosides, flavonoids, coumarins, condensed tannins, and saponins. Some of these phytochemicals have been related to antihypercholesterolemia, antidiabetic, antimenopause, anti-inflammatory, antiedema, anthelmintic, and kidney protective effects. Two widely prescribed drugs have been developed starting from temperate forage legumes, namely, the antithrombotic warfarin, inspired from sweet clover's coumarin, and the antidiabetic metformin, a derivative of sainfoin's guanidine. Available evidence suggests that temperate forage legumes are a potentially important resource for the extraction of active principles to be used as nutraceuticals and pharmaceuticals.

Anti-diabetic activity of Holothuria thomasi saponin

BACKGROUND

Diabetes mellitus represents a global health problem. It characterized by hyperglycemia that induces oxidative stress leading to a generation of free radicals. A wide variety of natural products in plants and other marine animals represent antioxidant activity and other health benefits like those of sea cucumber. Therefore, this study aimed to investigate the antidiabetic activity of glycosidic compound - saponin - derived from the Egyptian sea cucumber, Holothuria thomasi.

MATERIALS AND METHODS

Saponin has been extracted from the Egyptian sea cucumber and confirmed by hemolysis, Salkowski tests, FT/IR, UV and GC-MS analysis. Eighty white female albino rats were divided into four equal groups. The first two groups of rats; control normal and control normal saponin-treated groups. The last two groups which were made diabetic by intraperitoneal injection of streptozotocin had one diabetic control and the other diabetic group that got 300mg/kg B.wt. of saponin extract after Thirty-five days after diabetes induction and lasted for six weeks.

RESULTS

The functional group of saponin extract which established with FT/IR spectroscopy demonstrated the presence of saponin in the extracted materials as shown in the peak of the functional group in relevance to the standard one. The UV spectra revealed that λ_max of saponin extract was 282nm which in accordance to the standard saponin. Also, GC-MS analysis indicated that the aglycone part of saponin was methyl esters of octadecanoic acid. Saponin extract significantly decreased serum glucose, α-amylase activity, adiponectin, IL-6, TNF-α concentrations and liver L-MDA. However, serum insulin and liver glycogen levels were significantly increased as compared with the diabetic non-treated groups. The histopathological results supported that saponin extract markedly reduced the degenerative change in β-cells.

CONCLUSIONS

This study, therefore, depicts that the Egyptian Holothuria thomasi, sea cucumber saponin as a hypoglycemic agent with the potential to normalize aberrant biochemical parameters and preserved the normal histological architecture of the islets cells of pancreatic tissues.

Effects of alfalfa saponin extract on mRNA expression of Ldlr, LXRα, and FXR in BRL cells

We studied the effects of alfalfa saponin extract (ASE) on low density lipoprotein receptor (Ldlr), liver X receptor α (LXRα), and farnesoid X receptor (FXR) in normal and hyperlipidemic Buffalo rat liver (BRL) cells. Normal and hyperlipidemic BRL cells were divided into eight groups: normal, or normal cells treated with 50, 100, and 150 mg/L ASE, hyperlipidemic, or hyperlipidemic cells treated with 50, 100, and 150 mg/L ASE. After treatment for 24 h, Ldlr, LXRα, and FXR mRNA expression levels were measured by quantitative real-time polymerase chain reaction (qRT-PCR). Data showed that mRNA expression of Ldlr in normal BRL cells was significantly up-regulated by ASE treatment and mRNA expressions of LXRα and FXR were significantly down-regulated both in normal and hyperlipidemic BRL cells after ASE treatment. Thus, ASE might ameliorate hepatic steatosis by regulating genes involved in cholesterol metabolism, including up-regulation of Ldlr as well as down-regulation of LXRα and FXR.

Effect of testosterone deficiency on cholesterol metabolism in pigs fed a high-fat and high-cholesterol diet

Background

Testosterone deficiency is associated with increased serum cholesterol levels. However, how testosterone deficiency precisely affects cholesterol metabolism remains unclear. Therefore, in the current study, we examined the effect of testosterone deficiency on cholesterol metabolism and liver gene expression in pigs fed a high-fat and high-cholesterol (HFC) diet.

Methods

Sexually mature male miniature pigs (6–7 months old) were randomly divided into 3 groups as follows: intact male pigs fed an HFC diet (IM + HFC), castrated male pigs fed an HFC diet (CM + HFC), and castrated pigs with testosterone replacement fed an HFC diet (CM + HFC + T). Serum testosterone levels and lipid profiles were measured, and gene expression levels associated with hepatic cholesterol metabolism were determined. Furthermore, total hepatic cholesterol contents and the activities of enzymes mediating hepatic cholesterol metabolism were measured.

Results

Serum testosterone levels were significantly decreased in CM + HFC pigs, and testosterone replacement attenuated castration-induced testosterone deficiency. Castration significantly increased the serum levels of total cholesterol, low-density lipoprotein cholesterol and triglycerides, as well as hepatic lipid contents in pigs fed an HFC diet. Compared with IM + HFC and CM + HFC + T pigs, low-density lipoprotein receptor (LDLR) mRNA expression and protein levels were significantly decreased in the livers of CM + HFC pigs. In contrast, we found that compared with IM + HFC pigs, hepatic proprotein convertase subtilisin/kexin type 9 (PCSK9) mRNA and serum PCSK9 protein levels were significantly increased in CM + HFC pigs. Moreover, testosterone treatment reversed the increase in PCSK9 expression in CM + HFC pigs. However, neither castration nor testosterone replacement affected the expression of the other hepatic genes that were tested.

Conclusions

This study demonstrated that castration-induced testosterone deficiency caused severe hypercholesterolemia in pigs fed an HFC diet; furthermore, these effects could be reversed by testosterone replacement therapy. Altered hepatic PCSK9 and LDLR expression, resulting in reduced LDL-cholesterol clearance, may contribute to the increased serum cholesterol levels induced by testosterone deficiency and an HFC diet. These results deepen our understanding of the underlying molecular mechanisms that mediate the effects of testosterone deficiency on cholesterol metabolism.

Transcriptomic analysis of hepatic responses to testosterone deficiency in miniature pigs fed a high-cholesterol diet

Background

Recent studies have indicated that low serum testosterone levels are associated with increased risk of developing hepatic steatosis; however, the mechanisms mediating this phenomenon have not been fully elucidated. To gain insight into the role of testosterone in modulating hepatic steatosis, we investigated the effects of testosterone on the development of hepatic steatosis in pigs fed a high-fat and high-cholesterol (HFC) diet and profiled hepatic gene expression by RNA-Seq in HFC-fed intact male pigs (IM), castrated male pigs (CM), and castrated male pigs with testosterone replacement (CMT).

Results

Serum testosterone levels were significantly decreased in CM pigs, and testosterone replacement attenuated castration-induced testosterone deficiency. CM pigs showed increased liver injury accompanied by increased hepatocellular steatosis, inflammation, and elevated serum alanine aminotransferase levels compared with IM pigs. Moreover, serum levels of total cholesterol, low-density lipoprotein cholesterol, and triglycerides were markedly increased in CM pigs. Testosterone replacement decreased serum and hepatic lipid levels and improved liver injury in CM pigs. Compared to IM and CMT pigs, CM pigs had lower serum levels of superoxide dismutase but higher levels of malondialdehyde. Gene expression analysis revealed that upregulated genes in the livers of CM pigs were mainly enriched for genes mediating immune and inflammatory responses, oxidative stress, and apoptosis. Surprisingly, the downregulated genes mainly included those that regulate metabolism-related processes, including fatty acid oxidation, steroid biosynthesis, cholesterol and bile acid metabolism, and glucose metabolism. KEGG analysis showed that metabolic pathways, fatty acid degradation, pyruvate metabolism, the tricarboxylic acid cycle, and the nuclear factor-kappaB signaling pathway were the major pathways altered in CM pigs.

Conclusions

This study demonstrated that testosterone deficiency aggravated hypercholesterolemia and hepatic steatosis in pigs fed an HFC diet and that these effects could be reversed by testosterone replacement therapy. Impaired metabolic processes, enhanced immune and inflammatory responses, oxidative stress, and apoptosis may contribute to the increased hepatic steatosis induced by testosterone deficiency and an HFC diet. These results deepened our understanding of the molecular mechanisms of testosterone deficiency-induced hepatic steatosis and provided a foundation for future investigations.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-015-1283-0) contains supplementary material, which is available to authorized users.

The positive regulatory roles of the TIFY10 proteins in plant responses to alkaline stress

The TIFY family is a novel plant-specific protein family, and is characterized by a conserved TIFY motif (TIFF/YXG). Our previous studies indicated the potential roles of TIFY10/11 proteins in plant responses to alkaline stress. In the current study, we focused on the regulatory roles and possible physiological and molecular basis of the TIFY10 proteins in plant responses to alkaline stress. We demonstrated the positive function of TIFY10s in alkaline responses by using the AtTIFY10a and AtTIFY10b knockout Arabidopsis, as evidenced by the relatively lower germination rates of attify10a and attify10b mutant seeds under alkaline stress. We also revealed that ectopic expression of GsTIFY10a in Medicago sativa promoted plant growth, and increased the NADP-ME activity, citric acid content and free proline content but decreased the MDA content of transgenic plants under alkaline stress. Furthermore, expression levels of the stress responsive genes including NADP-ME, CS, H⁺-ppase and P5CS were also up-regulated in GsTIFY10a transgenic plants under alkaline stress. Interestingly, GsTIFY10a overexpression increased the jasmonate content of the transgenic alfalfa. In addition, we showed that neither GsTIFY10a nor GsTIFY10e exhibited transcriptional activity in yeast cells. However, through Y2H and BiFc assays, we demonstrated that GsTIFY10a, not GsTIFY10e, could form homodimers in yeast cells and in living plant cells. As expected, we also demonstrated that GsTIFY10a and GsTIFY10e could heterodimerize with each other in both yeast and plant cells. Taken together, our results provided direct evidence supporting the positive regulatory roles of the TIFY10 proteins in plant responses to alkaline stress.

Red yeast rice repairs kidney damage and reduces inflammatory transcription factors in rat models of hyperlipidemia

Xuezhikang (XZK), an extract of red yeast rice, has been widely used for the management of hyperlipidemia and coronary heart disease (CHD); however, the effects of XZK treatment on kidney injury have not yet been fully identified. The aim of the current study was to evaluate the effects of XZK on the kidneys and investigate the related mechanisms in a rat model of hyperlipidemia. Thus, the effect on inflammatory transcription factors and kidney damage was investigated with in vitro and in vivo experiments on hyperlipidemic rats following XZK treatment. The results revealed that the plasma levels of total cholesterol (TC), triglycerides (TG) and low-density lipoprotein-cholesterol (LDL-C) were significantly decreased, while the levels of high-density lipoprotein-cholesterol (HDL-C) were significantly upregulated in the XZK treatment group, as compared with those in the hyperlipidemia group (P<0.05). In addition, the results demonstrated that XZK was able to repair the kidney damage caused by hyperlipidemia. Furthermore, the expression levels of the inflammatory transcription factors, tumor necrosis factor-α and interleukin-6, were shown to be reduced in the XZK group when compared with the hyperlipidemia group. In summary, XZK reduces kidney injury, downregulates the levels of TG, TC and LDL-C, as well as the expression levels of inflammatory transcription factors, and upregulates HDL-C. These results further the understanding of the molecular pathogenic mechanisms underlying hyperlipidemia and aid the development of XZK as an effective therapeutic agent for hyperlipidemia.