Ginsenoside Rg1 attenuates liver injury induced by D-galactose in mice.

The present study investigated the effect and underlying mechanisms of ginsenoside Rg1 (Rg1) in attenuating subacute liver injury induced by D-galactose (D-gal) in mice. Specific Pathogen Free (SPF) male C57BL/6J mice were randomly divided into 3 groups: i) D-gal-administration group (D-gal group), where the mice were intraperitoneally administrated with D-gal (120 mg/kg/day for 42 days); ii) D-gal + Rg1 group where the mice were treated with 120 mg/kg/day D-gal for 42 days and with Rg1 at a dose of 20 mg/kg/day for 35 days. The first dose of Rg1 was administered on the 8th day of treatment with D-gal; and iii) the normal control group, where the mice were injected with an equal volume of saline for 42 days. The day following the final injections in all groups, peripheral blood was collected and serum was prepared to measure the contents of aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin (TBiL), advanced glycation end products (AGEs) and 8-hydroxy-2 deoxyguanosine (8-OH-dG). Liver tissue homogenates were prepared to measure the contents of malondialdehyde (MDA) and glutathione (GSH), and the activities of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD). Paraffin section were prepared to observe the microscopic structure of the liver. Transmission electron microscopy was used to observe the ultrastructure of hepatocytes. Frozen section were prepared and stained with senescence-associated ß-galactosidase to detect the relative optical density value of senescence-associated markers. Compared with the D-gal group, the contents of AST, ALT, TBiL, AGEs and MDA significantly decreased in the D-gal + Rg1 group, while the activities of SOD and GSH-Px markedly increased, and liver injury and degenerative alterations of hepatocytes were reduced. Administration of Rg1 induced a protective effect on D-gal-induced liver injury in mice by inhibiting the oxidative stress, reducing DNA damage and decreasing the AGE content.

Alleviation of ginsenoside Rg1 on hematopoietic homeostasis defects caused by lead-acetate.

The hematopoietic system is one of the potential targets of lead intoxication. Recognition of the lead-related deleterious outcomes promotes us to explore the potential therapeutic intervention. Here, we show that ginsenoside Rg1 (Rg1), extracted from the Chinese herb Panax ginseng, remarkably ameliorates the lead acetate-caused hematological index distortion as well as advanced hematopoietic stem cells (HSCs) aging and aging associated inflammation response. Specifically, Rg1 administration alleviated the increment of aging associated p53-p21-Rb signaling in aged HSCs induced by lead acetate. It also led a reduction of the lead acetate-induced increased inflammation level in blood plasma, which also partly contribute the aged HSCs rejuvenation. In conclusion, our results indicate that ginsenoside Rg1 therapeutically alleviated the essential blood deficits and advanced HSCs aging by lead acetate exposure, by which it could be viewed as a potential candidate for lead acetate-caused blood toxicity treatment.

Downregulation of miR-214-3p May Contribute to Pathogenesis of Ulcerative Colitis via Targeting STAT6.

MicroRNAs (miRs) are small noncoding RNA molecules and recently have demonstrated that altered expression and functions are their tight association with ulcerative colitis (UC). Previous microarray study reported that miR-214 was downregulated in the sigmoid colon of patients with active UC, but the roles of miR-214 in the pathogenesis of UC remain to be elucidated. In this study, significant lower level of miR-214-3p and higher level of STAT6 in the intestinal mucosa of active UC patients compared with the health controls were confirmed by quantitative real-time PCR. Results of luciferase reporter assays and western blot demonstrated that miR-214-3p directly targets STAT6 and negatively regulates the expression of STAT6 at the posttranscriptional level. Furthermore, the expression of miR-214-3p was decreased in TNF-α treated HT29 cells and STAT6 protein level was increased in a time-dependent manner. Silenced STAT6 and upregulation of miR-214-3p could decrease the level of INF-γ in TNF-α treated HT29 cells. Additionally, the results of the present study indicate that miR-214-3p and STAT6 axis may be a novel therapeutic target for intestinal inflammation of patients with active UC.

Study on the Dynamic Biological Characteristics of Sca-1(+) Hematopoietic Stem and Progenitor Cell Senescence.

The researches in the dynamic changes of the progress of HSCs aging are very limited and necessary. In this study, male C57BL/6 mice were divided into 5 groups by age. We found that the superoxide damage of HSPCs started to increase from the middle age (6 months old), with notably reduced antioxidation ability. In accordance with that, the senescence of HSPCs also started from the middle age, since the self-renewal and differentiation ability remarkably decreased, and senescence-associated markers SA-ß-GAL increased in the 6-month-old and the older groups. Interestingly, the telomere length and telomerase activity increased to a certain degree in the 6-month-old group. It suggested an intrinsic spontaneous ability of HSPCs against aging. It may provide a theoretical and experimental foundation for better understanding the senescence progress of HSPCs. And the dynamic biological characteristics of HSPCs senescence may also contribute to the clinical optimal time for antiaging drug intervention.

[Biological mechanisms of human-derived leukemia stem cells senescence regulated by Angelica sinensis polysaccharide].

OBJECTIVE: To explore the biological mechanisms underlying Angelica sindsis polysaccharide (ASP) -induced aging of human-derived leukemia stem cells (LSCs) in vitro. METHOD: Acute myelogenous leukemia stem cells were isolated by magnetic activated cell sorting (MACS). The ability of LSC proliferation treated by various concentration of ASP(20-80 mg · L(-1)) in vitro for 48 hours were tested using cell counting Kit-8 ( CCK8) , colony forming were evaluated by methylcellulose CFU assay. The ultra structure changes of AML CD34+ CD38- cells were analyzed by transmission electron microscopy. The aging cells were detected with senescence-ß-galactosidase Kit staining. Expression of aging-related p53, p21, p16, Rb mRNA and P16, Rb, CDK4 and Cyclin E protein were detected by quantitative reverse transcription polymerase chain reaction( qRT-PCR) and Western blotting, respectively. RESULT: The purity of the CD34 + CD38 - cells is (91.15 ± 2.41)% after sorted and showed good morphology. The proliferation of LSC was exhibited significantly concentration-dependent inhibited after exposure to various concentration of ASP. Treated by 40 mg · L(-1) ASP for 48 hours, the percentage of positive cells stained by SA-ß-Gal was dramatically increased (P < 0.01) and the colony-formed ability has been weakened (P < 0.01). The observation of ultrastructure showed that cell heterochromatin condensation and fragmentation, mitochondrial swelling, lysosomes increased in number. Aging-related p53, p21, p16, Rb and P16, Rb were up-regulated, protein regulatory cell-cycle CDK4 and Cyclin E were down-regulated. ASP may induce the senescence of LSCs effectively in vitro, P16-Rb cell signaling pathway play a significant role in this process. CONCLUSION: ASP can induce human leukemia stem cell senescence in vitro, the mechanism involved may be related to ASP regulation P16-Rb signaling pathways.

Mitochondria defects are involved in lead-acetate-induced adult hematopoietic stem cell decline.

Occupational high-grade lead exposure has been reduced in recent decades as a result of increased regulation. However, environmental lead exposure remains widespread, and is associated with severe toxicity implicated in human diseases. We performed oral intragastric administration of various dose lead acetate to adult Sprague Dawley rats to define the role of lead exposure in hematopoietic stem cells (HSCs) function, and to clarify its underlying mechanism. Lead acetate-exposed rats exhibited developmental abnormalities in myeloid and lymphoid lineages, and a significant decline in immune functions. It also showed HSCs functional decline associated with senescent phenotype with low grade lead acetate exposure or apoptotic phenotype with relative higher grade dose exposure. Mechanistic exploration showed a significant increase in reactive oxygen species (ROS) in the lead acetate-exposed CD90(+)CD45(-) compartment, which correlated with functional defects in cellular mitochondria. Furthermore, in vivo treatment with the antioxidant vitamin C led to reversion of the CD90(+)CD45(-) compartment functional decline. These results indicate that lead acetate perturbs the hematopoietic balance of adult HSCs, associated with cellular mitochondria defects, increased intracellular ROS generation.

[Protective effect of Angelica sinensis polysaccharides on subacute renal damages induced by D-galactose in mice and its mechanism].

To explore the protective effect of Angelica sinensis polysaccharides(ASP) on subacute renal damages induced by D-galactose in mice and its mechanism. Male C57BL/6J mice were randomly divided into 3 groups, with 10 mice in each group. The D-galactose model group was subcutaneously injected with D-galactose (120 mg x kg(-1)), qd x 42; the ASP + D-galactose model group was intraperitoneally injected with ASP since the 8th day of the replication of the D-galactose model, qd x 35; and the normal control group was subcutaneously injected with saline at the same dose and time. On the 2nd day of after the injection, the peripheral blood was collected to measure the content of BUN, Crea, UA, Cys-C; paraffin sections were made to observe the renal histomorphology by HE staining; senescence-associated ß-g-alactosidase (SA-ß-Gal) stain was used to observe the relative optical density (ROD) in renal tissues; transmission electron microscopy was assayed to observe the renal ultrastructure; the renal tissue homogenate was prepared to measure the content of SOD, GSH-PX, MDA; the content of AGEs and 8-OH-dG were measured by ELISA. According to the result, compared with the D-galactose model group, the ASP + D-galactose model group showed obviously decreases in the content of BUN, Crea, UA, Cysc, AGES, 8-OH-dG, the number of hardening renal corpuscle, renal capsular space and renal tubular lumen, ROD of SA-ß-Gal staining positive kidney cells, mesangial cells, basement membrane thickness, podocyte secondary processes fusion and MDA and increases in the number of normal renal corpuscle, ribosome and rough endoplasmic reticulum in podocytes, the activity of SOD and GSH-PX. In Conclusion, A. sinensis polysaccharides can antagonize kidney subacute damages induced by D-galactose in mice. Its protective mechanism may be correlated with the inhibition of the oxidative stress injury.

[Effect of combined administration of Angelica polysaccharide and cytarabine on liver of human leukemia NOD/SCID mouse model].

Leukemia is a type of malignant tumors of hematopoietic system with the abnormal increased immature leukemia cells showing metastasis and invasion ability. Liver is one of the main targets of the leukemia cells spread to, where they may continue to proliferate and differentiate and cause liver function damage, even liver failure. Our previous studies showed that Angelica polysscharides (APS), the main effective components in Angelica sinensis of Chinese traditional medicine, was able to inhibit the proliferation and induced differentiation of the leukemia cells, however, its effect on the liver during the treatment remains elucidated. In the present study, the human leukemia NOD/SCID mouse model were established by implantation human leukemia K562 cells line, then the leukemia mouse were treated with APS, Ara-c or APS + Ara-c respectively by peritoneal injection for 14 days, to explore the effect and mechanism of the chemicals on the mouse liver. Compared to the human leukemia NOD/SCID mouse model group with the treatments of APS, Ara-c and APS + Ara-c, We found that severe liver damage and pathological changes of the liver were able to alleviate: First, the number of white blood cells in the peripheral blood was significantly lower and with less transplanted K562 leukemia cells; Second, liver function damage was alleviated as liver function tests showed that alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total bilirubin (TBiL) were significantly reduced, while the albumin (Alb) was notably increased; Third, liver antioxidant ability was improved as the activities of the antioxidant enzymes glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) were significantly increased, and the contents of GSH and malonaldehyde (MDA) were decreased significantly in the liver; Fourth, the inflammation of the liver was relieved as the level of IL-1beta and IL-6, the inflammatory cytokines, were decreased significantly in the liver. Fifth, liver index was increased as the pathological observation showed that leukemia cells with diffused infiltration into the liver lobules were significantly reduced and with a remarkable increase of apoptotic positive cell rate by TUNEL test. Furthermore, the APS + Ara-c combined administration showed an even more significant positive effect. In conclusion, the APS, Ara-c therapy reduced the accumulation of leukemia cells within the liver, reduced the liver function damage and levels of inflammatory factors, improved antioxidant capacity of the liver tissue and thus alleviate the pathological changes of the liver. Moreover, the APS + Ara-c combination therapy may have an additive effect.