IGF-1 polymorphisms modulate the susceptibility to osteonecrosis of the femoral head among Chinese Han population

Emerging roles of growth factors in osteonecrosis of the femoral head

Osteonecrosis of the femoral head (ONFH) is a potentially disabling orthopedic condition that requires total hip arthroplasty in most late-stage cases. However, mechanisms underlying the development of ONFH remain unknown, and the therapeutic strategies remain limited. Growth factors play a crucial role in different physiological processes, including cell proliferation, invasion, metabolism, apoptosis, and stem cell differentiation. Recent studies have reported that polymorphisms of growth factor-related genes are involved in the pathogenesis of ONFH. Tissue and genetic engineering are attractive strategies for treating early-stage ONFH. In this review, we summarized dysregulated growth factor-related genes and their role in the occurrence and development of ONFH. In addition, we discussed their potential clinical applications in tissue and genetic engineering for the treatment of ONFH.

Spontaneous osteonecrosis of the jaw in a β-Thalassemia intermedia patient

The resultant anemia in hemoglobinopathies like thalassemia can lead to expansion of the bone marrow cavities due to compensatory hyperplasia. This article reports a case of spontaneous osteonecrosis of the left maxillary alveolus in a patient with β-Thalassemia intermedia. The area affected presented as areas of osteosclerosis on the radiographic examination and sequestrectomy of the left maxillary alveolus was performed after consultation with his hematologist. The exact pathogenesis for the osteonecrosis is unclear. One possible postulation for the cause of osteonecrosis in our case could be that the alveolar bone suffered ischemic infarction secondary to occlusion of the microvasculature within the expanded cancellous bone.

Identification of an IGF1 mutation (c.15+3G>A) in familial osteonecrosis of the femoral head: A case report

RATIONALE

Osteonecrosis of the femoral head is a common orthopedic disease. Some studies have shown that osteonecrosis of the femoral head is related to susceptibility genes, but there are few reports of familial osteonecrosis of the femoral head. Here, we reported two first-degree relatives with osteonecrosis of the femoral head.

PATIENT CONCERNS

A 27-year-old man with bilateral hip pain was diagnosed with osteonecrosis of the femoral head. The patient's mother also had a history of this disease.

DIAGNOSES

Whole exome sequencing revealed the same mutation (c.15+3G>A) in the insulin-like growth factor 1 (IGF1) gene of the proband and his mother but not in his elder sister.

INTERVENTIONS

The patient underwent bilateral total hip arthroplast.

OUTCOMES

The patient recovered well, and was discharged.

LESSONS

We found a heterozygous mutation (c.15+3G>A) in IGF1 in this family, which could be related to osteonecrosis of the femoral head. Early genetic counseling and gene locus detection could, thus, prove helpful for early diagnosis of osteonecrosis of the femoral head.

Down-regulated microRNA-141 facilitates osteoblast activity and inhibits osteoclast activity to ameliorate osteonecrosis of the femoral head via up-regulating TGF-β2

Osteonecrosis of the femoral head (ONFH) is a pathological process that initially occurs in the weight-bearing field of the femoral head. Due to the unknown pathogenesis, this study was for the investigation of the effect of microRNA-141 (miR-141) targeting transforming growth factor-β2 (TGF-β2) on regulating osteoblast activity and osteoclast activity in steroid-induced ONFH.Tissues of ONFH and normal femoral head were collected for detecting the expression of miR-141 and TGF-β2. A rat model of ONFH was constructed by injection of hormones, and transfected with miR-141 inhibitors and overexpressed TGF-β2. The apoptosis of bone cells was detected by TUNEL staining. The expression of osteoprotegerin (OPG), osteoprotegerin ligand (OPGL), Bcl-2, Bax, Runx2, BMP2 and RANK were detected.Highly expressed miR-141 and lowly expressed TGF-β2 existed in femoral head tissues in ONFH. Inhibited miR-141 resulted in elevated TGF-β2 in femoral head tissues in ONFH of rats. Depressed miR-141 or overexpressed TGF-β2 inhibited the apoptosis of bone cells of rats with ONFH and induced elevated OPG, Bcl-2, BMP2, Runx2 and declined OPGL, Bax and RANK expression in the femoral head tissues of rats with ONFH.Altogether, we find that down-regulated miR-141 promotes osteoblast activity and inhibits osteoclast activity to ameliorate ONFH via up-regulated TGF-β2 expression.