Search

Background: The decreased renal function is known to be associated with biological aging, of which the main pathological features are chronic inflammation and renal interstitial fibrosis. In previous studies, we reported that total saponins from Panax japonicus (SPJs) can availably protect acute myocardial ischemia. We proposed that SPJs might have similar protective effects for aging-associated renal interstitial fibrosis. Thus, in the present study, we evaluated the overall effect of SPJs on renal fibrosis. Methods: Sprague-Dawley (SD) aging rats were given SPJs by gavage beginning from 18 months old, at 10 mg/kg/d and 60 mg/kg/d, up to 24 months old. After the experiment, changes in morphology, function and fibrosis of their kidneys were detected. The levels of serum uric acid (UA), β2-microglobulin (β2-MG) and cystatin C (Cys C) were assayed with ELISA kits. The levels of extracellular matrix (ECM), matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), inflammatory factors and changes of oxidative stress parameters were examined. Results: After SPJs treatment, SD rats showed significantly histopathological changes in kidneys accompanied by decreased renal fibrosis and increased renal function; As compared with those in 3-month group, the levels of serum UA, Cys C and β2-MG in 24-month group were significantly increased (p

Mesenchymal stem cells (MSCs) are multipotent progenitors that can differentiate into multiple lineages including osteoblastic lineage. Osteogenic differentiation of MSCs is a cascade that recapitulates most, if not all, of the molecular events occurring during embryonic skeletal development, which is regulated by numerous signaling pathways including bone morphogenetic proteins (BMPs). Through a comprehensive analysis of the osteogenic activity, we previously demonstrated that BMP9 is the most potent BMP for inducing bone formation from MSCs both in vitro and in vivo. However, as one of the least studied BMPs, the essential mediators of BMP9-induced osteogenic signaling remain elusive. Here we show that BMP9-induced osteogenic signaling in MSCs requires intact Notch signaling. While the expression of Notch receptors and ligands are readily detectable in MSCs, Notch inhibitor and dominant-negative Notch1 effectively inhibit BMP9-induced osteogenic differentiation in vitro and ectopic bone formation in vivo. Genetic disruption of Notch pathway severely impairs BMP9-induced osteogenic differentiation and ectopic bone formation from MSCs. Furthermore, while BMP9-induced expression of early-responsive genes is not affected by defective Notch signaling, BMP9 upregulates the expression of Notch receptors and ligands at the intermediate stage of osteogenic differentiation. Taken together, these results demonstrate that Notch signaling may play an essential role in coordinating BMP9-induced osteogenic differentiation of MSCs., Bone morphogenetic protein (BMP) 9 is a potent inducer of osteogenic differentiation from mesenchymal stem cells, but the mediators of BMP9-induced osteogenesis remain elusive. Here, the authors show that inhibition of Notch1 signaling effectively diminishes BMP9-induced osteogenesis. Genetic disruption of Notch pathway severely impairs BMP9-induced bone formation. Thus, these results demonstrate that Notch signaling may play an essential role in coordinating osteogenic differentiation.

Background: In the present research, we aimed to investigate the effects of total saponins from Panax japonica (TSPJ) on adipocyte inflammation and insulin resistance induced by a high-fat diet (HFD). Moreover, its underlying mechanism was also further explored. Methods: C57/BL mice were randomly divided into four groups as follows: normal diet (ND) group, HFD group, and two TSPJ + HFD groups (30 mg/kg and 90 mg/kg). Insulin resistance test, glucose tolerance test, fat index analysis, histopathological assay, Western blotting analysis, and real-time PCR were performed to analyze the protective effect of TSPJ on adipose tissue. The protective mechanism of TSPJ on 3T3-L1 cells was studied in vitro by Oil Red O staining, 2-deoxyglucose uptake measurement etc. . Findings: In vivo, we found that TSPJ inhibited the activation of NF-κB and increase the transcription of p-AKT, leading to reduced inflammation and improved the sensitivity of adipocytes to insulin. In vitro evaluation revealed that palmitic acid (PA) induced inflammation by activating the NF-κB pathway, and induced insulin resistance by affecting the expressions of p-AKT in adipocytes. TSPJ pre-treatment could prevent such these response in a dose-dependent manner. TSPJ might exert its protective effect on 3T3-L1 cells by affecting the expression of AMPK. Interpretations: Our study showed that TSPJ could inhibit adipocyte inflammation by inhibiting NF-κB pathways. In addition, TSPJ could also affect the expressions of p-AKT to increase insulin sensitivity in adipocytes via targeting AMPK. Funding: This study was financially supported by the grants from National Natural Science Foundation of China. Declaration of Interests: The authors declare that they have no competing interests. Ethics Approval Statement: This study was financially supported by the grants from National Natural Science Foundation of China (Grant No. 81773959 to C.F. Yuan and No. 81974528 to C.F. Yuan) and Health commission of Hubei Province scientific research project in China. (Grant No. WJ2019H527 to C.F. Yuan).

Glomerular podocytes are highly specialized epithelial cells and play an essential role in establishing the selective permeability of the glomerular filtration barrier of kidney. Maintaining the viability and structural integrity of podocytes is critical to the clinical management of glomerular diseases, which requires a thorough understanding of podocyte cell biology. As mature podocytes lose proliferative capacity, a conditionally SV40 mutant tsA58-immortalized mouse podocyte line (designated as tsPC) was established from the Immortomouse over 20 years ago. However, the utility of the tsPC cells is hampered by the practical inconvenience of culturing these cells. In this study, we establish a user-friendly and reversibly-immortalized mouse podocyte line (designated as imPOD), on the basis of the tsPC cells by stably expressing the wildtype SV40 T-antigen, which is flanked with FRT sites. We show the imPOD cells exhibit long-term high proliferative activity, which can be effectively reversed by FLP recombinase. The imPOD cells express most podocyte-related markers, including WT-1, Nephrin, Tubulin and Vinculin, but not differentiation marker Synaptopodin. The imPOD cells do not form tumor-like masses in vivo. We further demonstrate that TGFβ1 induces a podocyte injury-like response in the FLP-reverted imPOD cells by suppressing the expression of slit diaphragm-associated proteins P-Cadherin and ZO-1 and upregulating the expression of mesenchymal markers, α-SMA, Vimentin and Nestin, as well as fibrogenic factors CTGF and Col1a1. Collectively, our results strongly demonstrate that the newly engineered imPOD cells should be a valuable tool to study podocyte biology both under normal and under pathological conditions. Keywords: Chronic kidney disease, FLP recombinase, Glomerular disease, Glomerulus, Immortalization, Nephropathy, Podocyte, SV40 T antigen

Mesenchymal stem cells (MSCs) are multipotent stem cells and capable of differentiating into multiple cell types including osteoblastic, chondrogenic and adipogenic lineages. We previously identified BMP9 as one of the most potent BMPs that induce osteoblastic differentiation of MSCs although exact molecular mechanism through which BMP9 regulates osteogenic differentiation remains to be fully understood. Here, we seek to develop a recombinant adenovirus system to optimally silence mouse BMP9 and then characterize the important role of BMP9 in osteogenic differentiation of MSCs. Using two different siRNA bioinformatic prediction programs, we design five siRNAs targeting mouse BMP9 (or simB9), which are expressed under the control of the converging H1 and U6 promoters in recombinant adenovirus vectors. We demonstrate that two of the five siRNAs, simB9-4 and simB9-7, exhibit the highest efficiency on silencing exogenous mouse BMP9 in MSCs. Furthermore, simB9-4 and simB9-7 act synergistically in inhibiting BMP9-induced expression of osteogenic markers, matrix mineralization and ectopic bone formation from MSCs. Thus, our findings demonstrate the important role of BMP9 in osteogenic differentiation of MSCs. The characterized simB9 siRNAs may be used as an important tool to investigate the molecular mechanism behind BMP9 osteogenic signaling. Our results also indicate that recombinant adenovirus-mediated expression of siRNAs is efficient and sustained, and thus may be used as an effective delivery vehicle of siRNA therapeutics. Keywords: BMP9, Bone formation, Mesenchymal stem cells, Osteogenic differentiation, RNA interference, Recombinant adenovirus, siRNA

While the human genome is pervasively transcribed

This study was undertaken to determine the effects of Pyracantha fortuneana (Maxim.) Li polysaccharides (PFP) on antioxidant and immune functions in mice. Results from this study showed that PFP administration significantly increased thymus and spleen indices, promoted splenocyte proliferation and natural killer (NK) cell activity, and elevated CD4 T cell numbers as well as CD4(+)/CD8(+) ratios. PFP also increased interleukin-2 (IL-2) levels, and decreased the levels of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) in splenocytes. In addition, PFP treatment led to remarkable increases in glutathione peroxidase (GSH-PX) and superoxide dismutase (SOD) activities, and dramatic decreases in malondialdehyde (MDA) levels in splenocytes. Moreover, PFP increased mRNA and protein expression of nuclear factor erythroid 2-related factor (Nrf2) in splenocytes. Taken together, these results suggest that PFP treatment enhances the immune function and decreases the oxidative stress in mice.

The potential protective effects of Phellinus ribis glucan (PRG) administration against immune injury due to free radical formation were evaluated in mice. The results showed that glucan administration significantly increased thymus and spleen indices, spleen lymphocyte proliferation and NK cells activity, as well as CD8 T cell numbers, and decreased CD4+/CD8+. In accordance with a previous study, glucan administration significantly enhanced plasma glutathione peroxidase, superoxide dismutases activity and reduced plasma thiobarbituric acid reactive species level. In conclusion, our results indicate that glucan administration improve immune function by its free radicals scavenging activity and reducing oxidative stress in mice.