Rehmannia Glutinosa Polysaccharide Regulates Bone Marrow Microenvironment via HIF-1α/NF-κB Signaling Pathway in Aplastic Anemia Mice.

Aplastic anemia (AA), a rare disorder, is associated with bone marrow microenvironment (BMM). Presently, AA treatment is of great difficulty. This study aimed to explore the mechanism of action of Rehmannia glutinosa polysaccharide (RGP) in AA. Busulfan was used to induce AA in BALB/c mice; blood cell count and Ray's Giemsa staining were used to assess the severity of hematopoietic failure; HE was performed to assess the pathological state of the marrow cavity; ELISA was performed to assess IL-4, IL-10, IL-6, IL-12, IL-1ß, TNF-α, MCP-1, VEGF, and EPO; and WB was performed to evaluate the effects of RGP on the HIF-1α/NF-κB signaling. Significant downregulation of hemocyte levels in the blood and nucleated cells in the bone marrow was reversed by RGP and Cyclosporine A (CA). Compared with the AA group, dilating blood sinusoids, inflammation, hematopoiesis, decreased bone marrow cells and megakaryocytes were alleviated by RGP and CA, and the HIF-1α/NF-κB signaling was inhibited too. Notably, RGP was more effective when used in combination with CA. In this study, we established a relationship between BMM and the HIF-1α/NF-κB signaling pathway and found that RGP regulates BMM by suppressing the activation of the HIF-1α/NF-κB signaling. Thus, RGP exerts a pharmacological effect on AA.

The mechanism study of inhibition effect of prepared Radix Rehmanniainon combined with Radix Astragali osteoporosis through PI3K-AKT signaling pathway

Purpose: To observe the mechanism of prepared Radix Rehmanniainon combined with Radix Astragali in treating osteoporosis. Methods: Osteoporosis rat model was established by bilateral ovariectomy combined with low-calcium diet feeding. Bone mineral density was measured by bone densitometer. Bone metabolism markers in serum were detected by enzyme linked immunosorbent assay (ELISA), bone tissue structure was observed by hematoxylin-eosin staining, and the effect of prepared Radix Rehmanniainon combined with Radix Astragali on PI3K-AKT signaling pathway was investigated by immunohistochemistry and reverse transcription polymerase chain reaction. Results: Compared with the model group, the bone tissue structure and imbalance of bone metabolism were improved, and the bone mineral density was significantly increased in the prepared Radix Rehmanniainon combined with Radix Astragali groups. After intervention with prepared Radix Rehmanniainon combined with Radix Astragali, the positive expression of PIK3CA and Akt1 in rat bone tissue was enhanced, and the expression levels of Akt1 mRNA were significantly increased. Conclusions: Prepared Radix Rehmanniainon combined with Radix Astragali may treat osteoporosis by activating PI3K/AKT pathway.

Effects of Rehmannia glutinosa polysaccharides on bone tissue structure and skeletal muscle atrophy in rats with disuse.

PURPOSE: To study effects of Rehmannia glutinosa polysaccharides (RGP) on bone tissue structure and skeletal muscle atrophy in rats with disuse. METHODS: A rat model of disuse osteoporosis combined with muscle atrophy was established by removing the bilateral ovaries of rats and fixing their hind limbs for a long time. Forty SD rats were administered intragastrically for 12 weeks. The bone histomorphometry parameters and the level of oxidative stress were measured. In addition, the changes of muscle atrophy F-box (MAFbx), muscle RING-finger protein-1 (MuRF1), forkhead box O1 (FOXO1) mRNA expression in skeletal muscle of rats were observed. RESULTS: RGP significantly increased the percentage of fluorescence perimeter and bone mineralization deposition rate of the second lumbar vertebrae of rats. It also significantly increased the wet weight ratio and muscle fiber cross-sectional area of the gastrocnemius muscle of rats. At the same time, RGP significantly increased the levels of super oxide dismutase (SOD) and catalase (CAT) in the skeletal muscle of rats, and reduced the content of malondialdehyde (MDA). Rehmannia glutinosa polysaccharides also significantly reduced the expression levels of FOXO1, MAFbx and MuRF1 mRNA in rat skeletal muscle. CONCLUSIONS: RGP could improve the bone structure of osteoporotic rats. It could also improve muscle that atrophy may be related to the inhibition of FOXO1-mediated ubiquitin-proteasome pathway.

Effects of Rehmannia glutinosa polysaccharides on bone tissue structure and skeletal muscle atrophy in rats with disuse

ABSTRACT Purpose To study effects of Rehmannia glutinosa polysaccharides (RGP) on bone tissue structure and skeletal muscle atrophy in rats with disuse. Methods A rat model of disuse osteoporosis combined with muscle atrophy was established by removing the bilateral ovaries of rats and fixing their hind limbs for a long time. Forty SD rats were administered intragastrically for 12 weeks. The bone histomorphometry parameters and the level of oxidative stress were measured. In addition, the changes of muscle atrophy F-box (MAFbx), muscle RING-finger protein-1 (MuRF1), forkhead box O1 (FOXO1) mRNA expression in skeletal muscle of rats were observed. Results RGP significantly increased the percentage of fluorescence perimeter and bone mineralization deposition rate of the second lumbar vertebrae of rats. It also significantly increased the wet weight ratio and muscle fiber cross-sectional area of the gastrocnemius muscle of rats. At the same time, RGP significantly increased the levels of super oxide dismutase (SOD) and catalase (CAT) in the skeletal muscle of rats, and reduced the content of malondialdehyde (MDA). Rehmannia glutinosa polysaccharides also significantly reduced the expression levels of FOXO1, MAFbx and MuRF1 mRNA in rat skeletal muscle. Conclusions RGP could improve the bone structure of osteoporotic rats. It could also improve muscle that atrophy may be related to the inhibition of FOXO1-mediated ubiquitin-proteasome pathway.

Rehmannia glutinosa oligosaccharide induces differentiation of bone marrow mesenchymal stem cells into cardiomyocyte-like cells.

The aim of this study was to observe the effect of Rehmannia glutinosa oligosaccharide (RGO) on differentiation of bone marrow mesenchymal stem cells (MSCs) into cardiomyocyte-like cells . Rat MSCs were isolated, treated, and grouped as follows: RGO treatment group, 5-azacytidine (5-aza) treatment group, RGO + 5-aza treatment group, and control group. Following a four-week induction period, cardiac troponin I (cTnI) levels in MSCs were quantified by chemiluminescence, and the levels of myocardial enzymes creatine kinase (CK) and creatine kinase isoenzyme-MB (CK-MB) were measured using a dry chemistry analyzer. The cTnI- and connexin 43 (Cx43)-positive MSC population was identified by immunofluorescence, and expression levels of cTnI and Cx43 were analyzed by western blots. Following induction, cTnI, CK, and CK-MB levels were significantly higher in the RGO + 5-aza group as compared with the RGO and 5-aza groups (P < 0.05). In addition, fluorescence intensity of cTnI and Cx43 was higher in the RGO + 5-aza group as compared with the RGO and 5-aza groups. No cTnI- or Cx43-positive cells were detected in the control group. Western blot analysis further confirmed that cTnI and Cx43 were not expressed in the control group, while cTnI and Cx43 was higher in the RGO + 5-aza group than in the RGO and 5-aza groups. These results suggest that MSCs can be induced by RGO to differentiate into cardiomyocyte-like cells in vitro, and that RGO in combination with 5-aza enhance differentiation of MSCs.

Cloning, molecular characterization, and expression analysis of a nucleoporin gene (rgNUP98-96) from Rehmannia glutinosa.

Nucleoporin 98 (NUP98) and nucleoporin 96 (NUP96) are essential components of the nuclear pore complex (NPC) in eukaryote cells. However, there is a lack of available information about complete Rehmannia glutinosa NUP98-96 (rgNUP98-96) sequences. Here, the full-length cDNA sequence of rgNUP96-98 was isolated from R. glutinosa using rapid amplification of cDNA ends (RACE) technology, based on a cloned cDNA sequence (GenBank accession No. JZ483329). The identified rgNUP98-96 was 3476 bp, and it encoded a 1041-amino acid peptide. The BLAST search analysis of rgNUP98-96 showed an intermediate degree of similarity (60-79%) to the NUP98-96 protein sequences of 34 other plants, including the dicotyledons Erythranthe guttata, Genlisea aurea, Coffea canephora, Nicotiana benthamiana, Solanum lycopersicum, and Solanum tuberosum. The phylogenetic analysis of NUP96-98 sequences indicated that R. glutinosa and E. guttata sequences shared the closest homology. The calculated molecular mass and predicted isolectric point of the complex protein were 117.6 kDa and 4.99, respectively. The secondary and three-dimensional structure studies illustrated that the rgNUP96-98 protein folded into a channel motif comprised of 34 alpha-helices, nine beta-strands, and several long loops. Using quantitative real-time PCR, the spatio-temporal expression patterns of rgNUP98-96 were analyzed in R. glutinosa, and the results indicated that rgNUP98-96 was highly expressed at the early stage of R. glutinosa tuberous root expansion, which is associated with a higher expression pattern in roots. The study provides a valuable foundation for further investigation of rgNUP96-98 molecular functions in R. glutinosa.