Application of Radix Rehmanniae Preparata Polysaccharide in Postmenopausal Osteoporosis

Abstract

The present application relates to the application of Radix Rehmanniae Preparata polysaccharide in postmenopausal osteoporosis, and relates to the application of active ingredients of traditional Chinese medicine in the treatment of bone metabolism diseases. The Radix Rehmanniae Preparata polysaccharide can improve the postmenopausal osteoporosis by up-regulating the expression of estrogen receptors and promoting the synthesis of estrogen.

Description

Technical Field

[0001] This invention relates to the application of active ingredients of traditional Chinese medicine in the treatment of bone metabolic diseases, and to the application of Rehmannia glutinosa polysaccharide in postmenopausal osteoporosis. Background Technology

[0002] Postmenopausal osteoporosis (PMOP) is a degenerative disease in postmenopausal women caused by the decline in ovarian function and estrogen levels, leading to damage to bone microstructure, reduced bone mass, and decreased bone density. It is characterized by high incidence, high disability rate, and high mortality rate. Its main manifestations include pain, bone fragility and increased risk of fractures, as well as anxiety and depression.

[0003] Studies show that the prevalence of postmenopausal osteoporosis (PMOP) in women over 50 years of age in my country is approximately 20%, while the risk of osteoporotic fractures in women is about 40%. Current treatments largely rely on hormone replacement therapy and bisphosphonates, but these have potential adverse reactions and adherence issues. For example, teriparatide increases the risk of hypercalcemia. Estrogen replacement therapy is an effective treatment for PMOP, but long-term use increases the risk of other diseases. Therefore, there is a need to develop new therapeutic drugs to effectively treat postmenopausal osteoporosis patients and reduce adverse reactions.

[0004] The primary pathogenesis of postmenopausal osteoporosis is a significant decline in estrogen levels. Before menopause, estrogen is mainly secreted by the ovaries. After menopause, due to the decline in ovarian function, estrogen is synthesized locally in the adrenal glands and non-gonadal tissues such as fat and bone cells, resulting in a substantial overall decrease in estrogen levels. This change directly affects bone metabolism balance, leading to increased bone resorption and decreased bone formation, which in turn causes bone loss and destruction of bone microstructure. Estrogen exerts its effects in different tissues through its two types of receptors (ERα and ERβ), with ERβ being widely expressed in bone tissue and playing a crucial role in regulating bone metabolism. Therefore, estrogen deficiency has a clear causal relationship with the development of osteoporosis. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides the application of Rehmannia glutinosa polysaccharide in postmenopausal osteoporosis. This Rehmannia glutinosa polysaccharide improves postmenopausal osteoporosis by upregulating estrogen receptor expression and promoting estrogen synthesis.

[0006] This invention provides the application of Rehmannia glutinosa polysaccharide in the preparation of a drug for treating postmenopausal osteoporosis.

[0007] Postmenopausal osteoporosis and senile osteoporosis are two distinct types with significant differences in etiology, symptoms, diagnosis, and treatment. Postmenopausal osteoporosis is caused by a sharp decline in estrogen levels. After menopause, ovarian function declines, estrogen deficiency leads to excessive osteoclast activity, resulting in rapid bone loss. Therefore, postmenopausal osteoporosis is characterized by rapid, acute, and drastic bone loss, primarily affecting the vertebral bodies and distal radius (cancellous bone). Senile osteoporosis, on the other hand, is caused by systemic aging. Age-related decline in calcium absorption, insufficient vitamin D synthesis, and osteoblast dysfunction result in reduced bone formation. Therefore, senile osteoporosis is characterized by slow, persistent, and systemic bone loss, with reductions in both cortical and cancellous bone. Therefore, medications for treating osteoporosis in the elderly primarily focus on promoting bone formation, while supplementing with active vitamin D and calcium as adjunctive therapies to improve calcium absorption and enhance bone formation. In contrast, medications for treating postmenopausal osteoporosis mainly focus on promoting estrogen and using estrogen-like substances to inhibit bone resorption, thereby quickly preventing rapid bone loss.

[0008] In one embodiment, the Rehmannia glutinosa polysaccharide treats postmenopausal osteoporosis by upregulating estrogen receptor expression and promoting estrogen synthesis.

[0009] In one embodiment, the drug further includes pharmaceutically acceptable excipients.

[0010] In one embodiment, the excipients include at least one of the following: excipients, lubricants, antioxidants, preservatives, binders, fillers, or thickeners.

[0011] In one embodiment, the dosage of Rehmannia glutinosa polysaccharide is ≥ 1g per kilogram of body weight.

[0012] In one embodiment, the dosage form of the drug is an oral preparation.

[0013] The present invention also provides a medicament for treating postmenopausal osteoporosis, comprising a pharmaceutically active ingredient and pharmaceutically acceptable excipients, wherein the pharmaceutically active ingredient is Rehmannia glutinosa polysaccharide.

[0014] In one embodiment, the excipients include at least one of the following: excipients, lubricants, antioxidants, preservatives, binders, fillers, or thickeners.

[0015] In one embodiment, the dosage of Rehmannia glutinosa polysaccharide in the drug is ≥ 1g per kilogram of body weight.

[0016] In one embodiment, the dosage form of the drug is an oral preparation.

[0017] Compared with the prior art, the present invention has the following beneficial effects: The present invention relates to the application of Rehmannia glutinosa polysaccharide in postmenopausal osteoporosis. This Rehmannia glutinosa polysaccharide improves postmenopausal osteoporosis by upregulating estrogen receptor expression and promoting estrogen synthesis, thereby providing a safe, natural, and hormone-free novel treatment option. Attached Figure Description

[0018] Figure 1 Representative two-dimensional and three-dimensional reconstructed images of the distal femur obtained by micro-CT scan; Figure 2 This is a schematic diagram showing the expression results of proteins related to bone tissue function. Detailed Implementation

[0019] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0021] Unless otherwise specified, all reagents, materials, and equipment used in this embodiment are commercially available; unless otherwise specified, all test methods are conventional test methods in this field.

[0022] Example I. Experimental Methods.

[0023] (1) Experimental grouping: Thirty 8-week-old SPF-grade female SD rats were randomly divided into three groups: sham operation group (sham, 10ml / kg / d of distilled water); model group (OVX, 10ml / kg / d of distilled water); and Rehmannia glutinosa polysaccharide group (OVX+RGP, 1g / 10ml / kg). Mice in each group were administered the medication by gavage for 12 consecutive weeks, and their food intake, water intake, and activity were observed daily.

[0024] (2) Preparation of Rehmannia polysaccharide solution: Rehmannia polysaccharide was purchased from Hubei Youfushui Biomedical Technology Co., Ltd., batch number Q20230411-002. 10g was added to 100ml of single-distilled water and dissolved by sonication to prepare a concentration of 100mg / ml. The Rehmannia polysaccharide solution was administered to rats by gavage at a dose of 10ml / kg of rat body weight.

[0025] (3) Bone density and Micro-CT 3D reconstruction: The right femur was preserved in 70% ethanol-saline solution and examined by micro-CT. The distal end of the right femur was scanned along its long axis at 360 degrees and 15.6 μm resolution to obtain continuous planar micro-CT images. Then, the 0-100 slices of the proximal end of the femoral growth plate were used as the region of interest for evaluating the trabecular bone structure, and about 1 mm of the mid-femur (100 slices) was used as the region of interest for evaluating the cortical bone. Bone tissue 1.0 mm distal to the 2.0 mm thick growth plate was selected as the region of interest (ROI) for 3D reconstruction. Bone tissue 1 mm distal to the femoral growth plate with a slice thickness of 3 mm was used as the region of interest for cancellous bone. Image information was obtained. Quantitative analysis of the images yielded the following data: BV / TV, Tb.Th, Tb.N, and Tb.Sp.

[0026] (4) Serum marker determination: After euthanizing rats, blood was collected and left to stand at 4°C for 4 hours before serum separation. The levels of bone formation marker PINP, bone resorption marker CTX-I, estradiol E2, and testosterone T in serum were detected by ELISA.

[0027] (5) Western blot analysis of tibial tissue: The right femur was taken and stored at -80℃. Protein was extracted using a bone protein extraction reagent. The Lowrry method was used for protein quantification. Western blot analysis was used to determine osteoclast-related proteins RANKL and TRAP; hormone-related proteins: ERα, ERβ, etc.

[0028] (6) Statistical Analysis: SPSS 24.0 software was used for statistical analysis. First, a normality test was performed. When P > 0.05, the sample data met the assumption of a normal distribution. Second, a homogeneity of variance test was performed. When P > 0.05, homogeneity of variance among the groups was established. After satisfying the requirements of normality and homogeneity of variance, analysis of variance (ANOVA) was performed. If the ANOVA was statistically significant, further pairwise comparisons were performed; if the homogeneity of variance condition was met, the LSD method was used for pairwise comparisons. If homogeneity was not met, a correction method was used for comparisons. Unless otherwise specified, Dunn's post-hoc test was used for pairwise comparisons of the treatment groups. Data are expressed as mean ± standard deviation. P < 0.05 was considered statistically significant.

[0029] II. Experimental Results.

[0030] (1) Micro-CT results: The results are as follows Figure 1 As shown, Figure 1This study demonstrates the ameliorative effect of Rehmannia glutinosa polysaccharide (RGP) on an osteoporosis model in ovariectomized (OVX) rats. Compared with the sham group, the OVX group showed a severe reduction in trabecular bone and severe damage to bone microstructure, while the OVX+RGP group showed significant improvement in these structural aspects, indicating the restorative effect of Rehmannia glutinosa polysaccharide on skeletal changes in osteoporosis.

[0031] Table 1 Quantitative Analysis Results of 3D Reconstructed Images

[0032] Note: ***P<0.001 vs sham, #P<0.05vs OVX; Table 1 shows that compared with the sham group, the OVX group had significantly lower bone volume fraction and trabecular bone number (P < 0.001), while the OVX+RGP group had significantly higher bone volume fraction and trabecular bone number (P < 0.05). Compared with the sham group, the OVX group had significantly lower trabecular bone thickness, while the OVX+RGP group had improved trabecular bone thickness (P < 0.05). Compared with the sham group, the OVX group had significantly increased trabecular bone separation (P < 0.001), while the OVX+RGP group had decreased trabecular bone separation. Therefore, Rehmannia glutinosa polysaccharide (RGP) can significantly improve ovariectomy-induced osteoporosis in rats, manifested by increased trabecular bone thickness and number, reduced trabecular bone spacing, and overall improved bone microstructure, demonstrating its potential therapeutic effect in preventing and treating postmenopausal osteoporosis.

[0033] (2) ELISA results: Table 2 Results of PINP, CTX-1, E2, T and other indicators

[0034] Note: ***P<0.001, **P<0.01 vs sham, #P<0.05, ###P<0.001vs OVX; As shown in Table 2, compared with the sham group, the levels of PINP, E2, and T in the OVX group were significantly decreased (P<0.01, P<0.001, P<0.001). Compared with the OVX group, the levels of PINP, E2, and T in the OVX+RGP treatment group showed varying degrees of recovery. Compared with the sham group, the level of CTX-1 in the OVX group was increased, while the level of CTX-1 in the OVX+RGP treatment group was significantly decreased (P<0.05).

[0035] The results suggest that Rehmannia glutinosa polysaccharides can influence bone resorption and bone metabolism by improving changes in hormone levels.

[0036] Table 3 Protein Quantification

[0037] like Figure 2 As shown in Table 3, compared with sham rats, the ERα / Erβ ratio in the OVX group was significantly decreased (P<0.05), while the ERα / Erβ ratio in the OVX+RGP group was significantly increased (P<0.05). Compared with sham rats, the TRAP ratio in the OVX group showed an increasing trend, with no statistical difference, while the RANKL ratio was significantly increased (P<0.001). Compared with OVX rats, the TRAP ratio in the OVX+RGP group showed a decreasing trend, with no statistical difference, while the RANKL ratio was significantly decreased (P<0.05).

[0038] The results suggest that Rehmannia glutinosa polysaccharides may improve bone metabolism disorders caused by postmenopausal estrogen deficiency by enhancing estrogen receptor expression, inhibiting RANKL-mediated osteoclast activation, and reducing TRAP activity.

[0039] (3) Conclusion: This invention provides an application of Rehmannia glutinosa polysaccharide in the treatment of postmenopausal osteoporosis. Through the action of its natural components, it can effectively regulate bone metabolism and improve bone density, exhibiting significant therapeutic effects, high safety, and suitability for long-term use.

[0040] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0041] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. The application of a polysaccharide from Rehmannia glutinosa in the preparation of a drug for treating postmenopausal osteoporosis.

2. According to claim 1, the Rehmannia glutinosa polysaccharide treats postmenopausal osteoporosis by upregulating estrogen receptor expression and promoting estrogen synthesis.

3. Use according to claim 1, characterized in that, The drug also includes pharmaceutically acceptable excipients.

4. Use according to claim 3, characterized in that, The excipients include at least one of the following: excipients, lubricants, antioxidants, preservatives, binders, fillers, or thickeners.

5. The use according to claim 1, characterized in that, In the aforementioned applications, the dosage of Rehmannia glutinosa polysaccharide is ≥ 1g per kilogram of body weight.

6. Use according to claim 1, characterized in that, The drug is an oral preparation.

7. A medicament for treating postmenopausal osteoporosis, characterized by, It includes a pharmaceutically active ingredient and pharmaceutically acceptable excipients, wherein the pharmaceutically active ingredient is Rehmannia glutinosa polysaccharide.

8. The medicament according to claim 7, characterized in that, The excipients include at least one of the following: excipients, lubricants, antioxidants, preservatives, binders, fillers, or thickeners.

9. The medicament according to claim 7, characterized in that, The dosage of Rehmannia glutinosa polysaccharide in the drug is ≥ 1g per kilogram of body weight.

10. The medicament according to claim 7, characterized in that, The drug is an oral preparation.

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