Stem-cell therapy for ovariectomy-induced osteoporosis in rats: a comparison of three treatment modalities

Emerging role of mesenchymal stem/stromal cells (MSCs) and MSCs-derived exosomes in bone- and joint-associated musculoskeletal disorders: a new frontier

Exosomes are membranous vesicles with a 30 to 150 nm diameter secreted by mesenchymal stem/stromal cells (MSCs) and other cells, such as immune cells and cancer cells. Exosomes convey proteins, bioactive lipids, and genetic components to recipient cells, such as microRNAs (miRNAs). Consequently, they have been implicated in regulating intercellular communication mediators under physiological and pathological circumstances. Exosomes therapy as a cell-free approach bypasses many concerns regarding the therapeutic application of stem/stromal cells, including undesirable proliferation, heterogeneity, and immunogenic effects. Indeed, exosomes have become a promising strategy to treat human diseases, particularly bone- and joint-associated musculoskeletal disorders, because of their characteristics, such as potentiated stability in circulation, biocompatibility, low immunogenicity, and toxicity. In this light, a diversity of studies have indicated that inhibiting inflammation, inducing angiogenesis, provoking osteoblast and chondrocyte proliferation and migration, and negative regulation of matrix-degrading enzymes result in bone and cartilage recovery upon administration of MSCs-derived exosomes. Notwithstanding, insufficient quantity of isolated exosomes, lack of reliable potency test, and exosomes heterogeneity hurdle their application in clinics. Herein, we will deliver an outline respecting the advantages of MSCs-derived exosomes-based therapy in common bone- and joint-associated musculoskeletal disorders. Moreover, we will have a glimpse the underlying mechanism behind the MSCs-elicited therapeutic merits in these conditions.

Anti-osteoporosis Effect of Fisetin against Ovariectomy Induced Osteoporosis in Rats: In silico, in vitro and in vivo Activity

Osteoporosis is a bone related disease that is characterised by bone loss that further increases the susceptibility to bone fractures and bone frailty due to disturbances in the micro-architecture of bone tissue. Fisetin (flavonoids) exhibited anti-inflammatory and antioxidative stress effects against various diseases. In this protocol, we make an effort to comfort the anti-osteoporosis effect of fisetin against ovariectomy (OVX) induced osteoporosis. A docking study of fisetin and alendronate on the estrogen (α and β) and vitamin D receptors was carried out. SaOS-2 (osteoblast like human) cells were used for the estimation of cell proliferation. The OVX induced OVX model was used and three doses of fisetin and alendronate was given to rats till 16 weeks. The hormone levels, bone turnover markers and biochemical parameters were estimated. Fisetin was docked into estrogen (α and β) and vitamin D receptors, resulting in stable complexes with lower binding scores. Fisetin significantly (p < 0.001) exhibited the induction of cell proliferation against the SaOS-2 cells. OVX induced osteoporosis rats exhibited a suppression of body weight and uterus index, after the Fisetin treatment. Fisetin treatment significantly (p < 0.001) improved the level of bone mineral content (BMC), bone mineral density (BMD) and biochemical parameters such as energy, maximum load, stiffness, young modules, maximum stress and reduced the level of 1,25(OH) 2 D3 and E 2 . Fisetin treatment significantly (p < 0.001) declined the level of phosphorus (P), calcium (Ca) and boosted the level of VitD. Fisetin treatment significantly (p < 0.001) reduced the malonaldehyde (MDA) level and enhanced the glutathione (GSH), catalase (CAT), superoxide dismutase (SOD) level in the bone, intestine and hepatic tissue. Fisetin treatment suppressed the cytokines, RANKL/OPG ratio, receptor activator of nuclear factor-κB ligand (RANKL) and improved the level of osteoprotegerin (OPG). The findings suggest that fisetin could be a beneficial phytoconstituent for the treatment and prevention of postmenopausal osteoporotic complications.

Evaluation of the Efficacy of Stem Cell Therapy in Ovariectomized Osteoporotic Rats Based on Micro-CT and Dual-Energy X-Ray Absorptiometry: A Systematic Review and Meta-Analysis

Objective

Osteoporosis is an abnormal bone metabolism disease characterized by microstructural degeneration of bone tissue and reduction in bone mass, resulting in increased brittleness of bone tissue and susceptibility to fracture. Due to the tissue regenerative potential of stem cell transplantation, it is now used in the treatment of various disease models such as osteoporosis. The purpose of this work is to carry out a systematic review and meta-analysis of the efficacy of stem cell therapy in ovariectomized (OVX) osteoporotic rats.

Methods

PubMed, Cochrane Library, ScienceDirect, Embase, CNKI, and Wanfang Databases were used to search for articles that met the inclusion criteria. Two researchers independently screened the articles that met the inclusion criteria. RevMan 5.3 and STATA 16.0 were used for data analysis. This meta-analysis was registered at INPLASY with reference number ID: INPLASY202150017.

Results

Thirteen eligible studies were selected, including 405 rats. The sources of stem cells are divided into four main categories: bone marrow mesenchymal stem cells (BMSCs), adipose-derived stem cells (ADSCs), amniotic membrane mesenchymal stem cells (AM-MSCs), and human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs). Compared with the OVX group, both stem cell transplantation groups had higher bone mineral density (BMD) (BMSCs: SMD = 2.01, 95% CI: [1.38, 2.63], P < 0.001, I² = 76.6%; ADSCs: SMD = 2.24, 95% CI: [0.79, 3.69], P = 0.003, I² = 86.7%) and bone volume/total volume (BV/TV) (hUCB-MSCs: SMD = 1.71, 95% CI: [0.97, 2.44], P < 0.001, I² = 0%; ADSCs: SMD = 2.16, 95% CI: [0.27, 4.04], P = 0.025, I² = 82.6%). In the BMSC treatment groups, the trabecular numbers (Tb.N) (SMD = 4.28, 95% CI: [0.91, 7.64], P = 0.013, I² = 94.9%) were significantly higher, whereas the results for trabecular thickness (Tb.Th) (SMD = 2.7, 95% CI: [-0.34, 5.73], P = 0.081, I² = 95.4%) and trabecular spacing (Tb.Sp) (SMD = −3.08, 95% CI: [-6.55, 0.38], P = 0.081, I² = 96.3%) were not statistically significant compared to those of the OVX group. The stem cell transplantation group had a low BMD, BV/TV, and Tb.N compared to the sham operation group.

Conclusion

Stem cell therapy may increase bone strength, bone volume, and the number of trabeculae in OVX osteoporotic rats. The results of this meta-analysis showed the potential therapeutic effect of stem cell transplantation in OVX osteoporotic rats, bringing new therapeutic ideas and directions to the clinical treatment of osteoporosis. Due to the limited number and quality of studies related to some outcomes, more high-quality RCTs are still needed in the future to complement the existing findings.

Efficacy of autologous bone marrow derived Mesenchymal stem cells (MSCs), osteoblasts and osteoblasts derived exosome in the reversal of ovariectomy (OVX) induced osteoporosis in rabbit model

Background: A recent study showed that OVX-induced osteoporosis was reversed after injection of osteoblasts cultured from the bone marrow in rats. The present study evaluated the effect of injecting MSCs, osteoblasts, and exosomes isolated from osteoblasts for the treatment of osteoporosis in the rabbit model. Methods: Osteoporosis was created in 40 rabbits by performing ovareictomy at 6 months of age, and 1 mg/kg body weight of methyl prednisolone sodium succinate was injected daily for 8 weeks. Animals were fed twice daily and were given water ad libitum. MSCs and osteoblasts were grown from the bone marrow as per the methodology described earlier. From osteoblasts, exosomes were extracted. After the 15th day, MSCs (Group 2), osteoblasts (Group 3), and exosomes (Group 4) were injected into 5 animals each, and 0.5 ml of normal saline were injected into the control group (Group 1). After 12 weeks (11 months of age), all the animals were euthanized. The whole femur and the lumbar vertebrae 3-5 were dissected out and were subjected to radiological assessment using high-resolution peripheral quantitative computerized tomography (HRpQCT). All parameters of the bone volume, trabecular number, thickness, and spacing were assessed using SPSS (Statistical Package for the Social Sciences), version 21.0, Chicago, Illinois. A p value of <0.05 was considered Statistically significant with a confidence interval (CI) of 95%. Results: Structural indices of the osteoblasts-injected animals were significantly better than the control group for the distal femur. The most significant improvement was seen in the osteoblasts, MSCs, and exosomes group in that order. The p value of all parameters was <0.0001 in the osteoblasts group, whereas the total and bone volume had a lower p value in the MSCs group. In the osteoblasts group, the positive changes were similar in the distal femur and lumbar vertebrae, but with MSCs and exosomes, the changes were more pronounced in the vertebral spine than the distal femur. Conclusions: This study shows that autologous bone marrow-derived osteoblasts have the robust influence of reversing OVX-induced osteoporosis in rabbits.