Adipose-derived stromal vascular fraction prevent bone bridge formation on growth plate injury in rat (in vivo studies) an experimental research

Laser-activated autologous adipose tissue-derived stromal vascular fraction restores spinal cord architecture and function in multiple sclerosis cat model

BACKGROUND

Multiple sclerosis (MS) is the most frequent non-traumatic neurological debilitating disease among young adults with no cure. Over recent decades, efforts to treat neurodegenerative diseases have shifted to regenerative cell therapy. Adipose tissue-derived stromal vascular fraction (SVF) comprises a heterogeneous cell population, considered an easily accessible source of MSCs with therapeutic potential in autoimmune diseases. This study aimed to assess the regenerative capacity of low-level laser-activated SVF in an MS cat model.

METHODS

Fifteen adult Persian cats were used in this study: Group I (control negative group, normal cats), Group II (EB-treated group, induced for MS by ethidium bromide (EB) intrathecal injection), and Group III (SVF co-treated group, induced for MS then treated with SVF on day 14 post-induction). The SVF was obtained after digesting the adipose tissue with collagenase type I and injecting it intrathecal through the foramen magnum.

RESULTS

The results showed that the pelvic limb's weight-bearing locomotion activity was significantly (P ≤ 0.05) recovered in Group III, and the Basso, Beattie, and Bresnahan (BBB) scores of hindlimb locomotion were significantly higher in Group III (14 ± 0.44) than Group II (4 ± 0.31). The lesion's extent and intensity were reduced in the magnetic resonance imaging (MRI) of Group III. Besides, the same group showed a significant increase in the expression of neurotrophic factors: BDNF, SDF and NGF (0.61 ± 0.01, 0.51 ± 0.01 and 0.67 ± 0.01, respectively) compared with Group II (0.33 ± 0.01, 0.36 ± 0.006 and 0.2 ± 0.01, respectively). Furthermore, SVF co-treated group revealed a significant (P ≤ 0.05) increase in oligodendrocyte transcription factor (Olig2) and myelin basic protein (4 ± 0.35 and 6 ± 0.45, respectively) that was decreased in group II (1.8 ± 0.22 and 2.9 ± 0.20, respectively). Moreover, group III showed a significant (P ≤ 0.05) reduction in Bax and glial fibrillary acidic protein (4 ± 0.53 and 3.8 ± 0.52, respectively) as compared with group II (10.7 ± 0.49 and 8.7 ± 0.78, respectively). The transmission electron microscopy demonstrated regular more compact, and markedly (P ≤ 0.05) thicker myelin sheaths (mm) in Group III (0.3 ± 0.006) as compared with group II (0.1 ± 0.004). Based on our results, the SVF co-treated group revealed remyelination and regeneration capacity with a reduction in apoptosis and axonal degeneration.

CONCLUSION

SVF is considered an easy, valuable, and promising therapeutic approach for treating spinal cord injuries, particularly MS.

Tissue engineering in growth plate cartilage regeneration: Mechanisms to therapeutic strategies

The repair of growth plate injuries is a highly complex process that involves precise spatiotemporal regulation of multiple cell types. While significant progress has been made in understanding the pathological mechanisms underlying growth plate injuries, effectively regulating this process to regenerate the injured growth plate cartilage remains a challenge. Tissue engineering technology has emerged as a promising therapeutic approach for achieving tissue regeneration through the use of functional biological materials, seed cells and biological factors, and it is now widely applied to the regeneration of bone and cartilage. However, due to the unique structure and function of growth plate cartilage, distinct strategies are required for effective regeneration. Thus, this review provides an overview of current research on the application of tissue engineering to promote growth plate regeneration. It aims to elucidates the underlying mechanisms by which tissue engineering promotes growth plate regeneration and to provide novel insights and therapeutic strategies for future research on the regeneration of growth plate.

Osteocalcin biomarker level evaluation on fracture healing with bone defect after stromal vascular fraction application in murine model

Introduction

Bone defect (3 mm in murine model) is a condition when the bone tissue cannot undergo a natural healing process caused by severe trauma, tumor, or irradiation. A bone defect is a challenge even for experienced Orthopaedic surgeons. Stromal vascular fraction (SVF) is a heterogeneous cell population derived from adipose tissue that results from minimal manipulation of the adipose tissue itself. Several studies have elucidated the effect of either SVF on bone defect healing. However, to the author's knowledge, there is no study evaluating the effect of SVF application on fracture healing, which was measured with osteocalcin biomarker. This study aims to evaluate the effect of SVF application on bone defect healing measured with osteocalcin as a biomarker of bone healing.

Materials and methods

This was an animal study involving twelve Wistar strain Rattus norvegivus. They were divided into three groups: negative group (normal rats), positive group (rats with bone defect and treated without SVF application), and SVF group (rats with bone defect and treated with SVF application). After 30 days, the rats were sacrificed, the osteocalcin biomarkers were evaluated. This biomarker was quantified using ELISA.

Results

Osteocalcin biomarker expressions were higher in the group treated with SVF application than those without using SVF. All comparisons of the SVF group and positive control group showed significant differences (p < 0.05).

Conclusion

SVF application could aid the healing process in a murine model with bone defect, marked by increased osteocalcin levels.

•

A study evaluating the effect of SVF application on fracture healing, measured with osteocalcin biomarker.

•

Osteocalcin is useful in the evaluation of bone turnover and the clinical setting of bone loss.

•

SVF could aid the healing process in a murine model with bone defect.

•

A bone defect is a challenge even for experienced Orthopaedic surgeons.

Effect of Stromal Vascular Fraction on Fracture Healing with Bone Defects by Examination of Bone Morphogenetic Protein-2 Biomarkers in Murine Model

BACKGROUND: Fractures and segmental bone defects are a significant cause of morbidity and a source of a high economic burden in healthcare. A severe bone defect (3 mm in murine model) is a devastating condition, which the bone cannot heal naturally despite surgical stabilization and usually requires further surgical intervention. The stromal vascular fraction (SVF) contains a heterogeneous collection of cells and several components, primarily: MSCs, HSCs, Treg cells, pericytic cells, AST cells, extracellular matrix, and complex microvascular beds (fibroblasts, white blood cells, dendritic cells, and intra-adventitial smooth muscular-like cells). Bone morphogenetic protein (BMP) is widely known for their important role in bone formation during mammalian development and confers a multifunctional role in the body, which has potential for therapeutic use. Studies have shown that BMPs play a role in the healing of large size bone defects. AIM: In this study, researchers aim to determine the effect of administering SVF from adipose tissue on the healing process of bone defects assessed based on the level biomarker of BMP-2. MATERIALS AND METHODS: This was an animal study involving 12 Wistar strain Rattus norvegivus. They were divided into three groups: Negative group (normal rats), positive group (rats with bone defect without SVF application), and SVF group (rats with bone defect with SVF application). After 30 days, the rats were sacrificed; the biomarkers that were evaluated are BMP-2. This biomarker was quantified using ELISA. RESULTS: BMP-2 biomarker expressions were higher in the SVF application group than in the group without SVF. All comparisons of the SVF group and positive control group showed significant differences (p = 0.026). CONCLUSION: SVF application could aid the healing process in a murine model with bone defect marked by the increased level of BMP-2 as a bone formation marker.

Enlightenment of Growth Plate Regeneration Based on Cartilage Repair Theory: A Review

The growth plate (GP) is a cartilaginous region situated between the epiphysis and metaphysis at the end of the immature long bone, which is susceptible to mechanical damage because of its vulnerable structure. Due to the limited regeneration ability of the GP, current clinical treatment strategies (e.g., bone bridge resection and fat engraftment) always result in bone bridge formation, which will cause length discrepancy and angular deformity, thus making satisfactory outcomes difficult to achieve. The introduction of cartilage repair theory and cartilage tissue engineering technology may encourage novel therapeutic approaches for GP repair using tissue engineered GPs, including biocompatible scaffolds incorporated with appropriate seed cells and growth factors. In this review, we summarize the physiological structure of GPs, the pathological process, and repair phases of GP injuries, placing greater emphasis on advanced tissue engineering strategies for GP repair. Furthermore, we also propose that three-dimensional printing technology will play a significant role in this field in the future given its advantage of bionic replication of complex structures. We predict that tissue engineering strategies will offer a significant alternative to the management of GP injuries.