MGF-19E peptide promoted proliferation, differentiation and mineralization of MC3T3-E1 cell and promoted bone defect healing

Clinical Peptidomics: Advances in Instrumentation, Analyses, and Applications

Extensive effort has been devoted to the discovery, development, and validation of biomarkers for early disease diagnosis and prognosis as well as rapid evaluation of the response to therapeutic interventions. Genomic and transcriptomic profiling are well-established means to identify disease-associated biomarkers. However, analysis of disease-associated peptidomes can also identify novel peptide biomarkers or signatures that provide sensitive and specific diagnostic and prognostic information for specific malignant, chronic, and infectious diseases. Growing evidence also suggests that peptidomic changes in liquid biopsies may more effectively detect changes in disease pathophysiology than other molecular methods. Knowledge gained from peptide-based diagnostic, therapeutic, and imaging approaches has led to promising new theranostic applications that can increase their bioavailability in target tissues at reduced doses to decrease side effects and improve treatment responses. However, despite major advances, multiple factors can still affect the utility of peptidomic data. This review summarizes several remaining challenges that affect peptide biomarker discovery and their use as diagnostics, with a focus on technological advances that can improve the detection, identification, and monitoring of peptide biomarkers for personalized medicine.

Effect of nHA-Coated Femoral Stem Prosthesis Combined with Platelet-Rich Plasma in Hemi Hip Replacement of Femoral Neck Fracture in the Elderly

Purpose

This study investigated the efficacy of nanohydroxyapatite- (nHA-) coated biological prosthesis combined with platelet-rich plasma (PRP) in hemi hip replacement of femoral neck fracture (FNF) in the elderly.

Methods

From September 2018 to September 2021, 102 elderly patients with FNF treated in our hospital were chosen and divided into two groups according to different intervention methods. Fifty-one patients in the bone cement group were treated with bone cement prosthesis, and the rest 51 patients in the observation group were treated with nHA biological prosthesis combined with PRP in hemi hip replacement. In order to explore the osteogenic effect of nHA and PRP, osteoblasts were cultured.

Results

It was found that nHA and PRP could both effectively promote the proliferation of osteoblasts and improve their mineralization ability, especially when used in combination. In the course of clinical therapy, we found that the use of biological prosthesis combined with PRP could effectively reduce the level of serum procollagen type I carboxy terminal peptide (PICP) and better improve the levels of bone alkaline phosphatase (BALP) and bone Gla protein (BGP), so as to reduce the bone conversion rate and promote the formation of new bone around the prosthesis. In addition, no significant difference was found in intraoperative bleeding, operation time, hospital stay, 48 h drainage volume, partial weight-bearing time, and complete weight-bearing time between two groups. Otherwise, the use of biological prosthesis could effectively avoid the occurrence of adverse reactions such as bone cement crisis and fracture around femoral prosthesis, so as to better restore the hip function and improve patients' life quality.

Conclusions

Therefore, in hemi hip replacement of FNF in the elderly, nHA biological prosthesis combined with PRP can effectively promote the formation of new bone around the prosthesis stem, so as to obtain good initial stability, enable patients to carry out early weight-bearing exercise, and effectively avoid adverse reactions caused by bone cement prosthesis, thus improving patients' hip function and life quality.

An injectable thermosensitive hydrogel with self-assembled peptide coupled with antimicrobial peptide for enhanced wound healing

Wound dressing based on thermosensitive hydrogel shows advantages over performed traditional dressings such as rapid reversible sol-gel-sol transition property and the capacity of filling the irregular wound area. Herein, RA-Amps...

Biological Functions of Let-7e-5p in Promoting the Differentiation of MC3T3-E1 Cells

MicroRNAs let-7c and let-7f, two members of the let-7 family, were involved in regulating osteoblast differentiation and have an important role in bone formation. Let-7e-5p, which also belonged to the let-7 family, presented in the differentiation of adipose-derived stem cells and mouse embryonic stem cells. However, the role of let-7e-5p in osteoblast differentiation was unclear. Thus, this study aimed to elucidate the function of let-7e-5p in osteoblast differentiation and its mechanism. Firstly, we found that the let-7e-5p mimic promoted osteoblast differentiation but not the proliferation of MC3T3-E1 cells by positively regulating the expression levels of osteogenic-associated genes (RUNX2, OCN, OPN, and OSX), the activity of ALP, and formation of mineralized nodules. Moreover, we ascertained that the let-7e-5p mimic downregulated the post-transcriptional expression of SOCS1 by specifically binding to the 3′ untranslated region of SOCS1 mRNA. Also, let-7e-5p-induced SOCS1 downregulation increased the protein levels of p-STAT5 and IGF-1, which were both modulated by SOCS1 molecules. Furthermore, let-7e-5p abrogated the inhibition of osteogenic differentiation mediated by SOCS1 overexpression. Therefore, these results suggested that let-7e-5p regulated the differentiation of MC3T3-E1 cells through the JAK2/STAT5 pathway to upregulate IGF-1 gene expression by inhibiting SOCS1. These findings may provide a new insight into the regulatory role of let-7e-5p in osteogenic differentiation and imply the existence of a novel mechanism underlying let-7e-5p-mediated osteogenic differentiation.

Role of Alternatively Spliced Messenger RNA (mRNA) Isoforms of the Insulin-Like Growth Factor 1 (IGF1) in Selected Human Tumors

Insulin-like growth factor 1 (IGF1) is a key regulator of tissue growth and development that is also implicated in the initiation and progression of various cancers. The human IGF1 gene contains six exons and five long introns, the transcription of which is controlled by two promoters (P1 and P2). Alternate promoter usage, as well as alternative splicing (AS) of IGF1, results in the expression of six various variants (isoforms) of mRNA, i.e., IA, IB, IC, IIA, IIB, and IIC. A mature 70-kDa IGF1 protein is coded only by exons 3 and 4, while exons 5 and 6 are alternatively spliced code for the three C-terminal E peptides: Ea (exon 6), Eb (exon 5), and Ec (fragments of exons 5 and 6). The most abundant of those transcripts is IGF1Ea, followed by IGF1Eb and IGF1Ec (also known as mechano-growth factor, MGF). The presence of different IGF1 transcripts suggests tissue-specific auto- and/or paracrine action, as well as separate regulation of both of these gene promoters. In physiology, the role of different IGF1 mRNA isoforms and pro-peptides is best recognized in skeletal muscle tissue. Their functions include the development and regeneration of muscles, as well as maintenance of proper muscle mass. In turn, in nervous tissue, a neuroprotective function of short peptides, produced as a result of IGF1 expression and characterized by significant blood-brain barrier penetrance, has been described and could be a potential therapeutic target. When it comes to the regulation of carcinogenesis, the potential biological role of different var iants of IGF1 mRNAs and pro-peptides is also intensively studied. This review highlights the role of IGF1 isoform expression (mRNAs, proteins) in physiology and different types of human tumors (e.g., breast cancer, cervical cancer, colorectal cancer, osteosarcoma, prostate and thyroid cancers), as well as mechanisms of IGF1 spliced variants involvement in tumor biology.

Synonymous Mutations of Porcine Igf1r Extracellular Domain Affect Differentiation and Mineralization in MC3T3-E1 Cells

Owing to the wide application of miniature pigs in biomedicine, the formation mechanism of its short stature must be elucidated. The insulin-like growth factor 1 receptor (IGF-1R), which receives signals through the extracellular domain (ECD) binding with ligands, is crucial in regulating cell growth and bone matrix mineralization. In this study, two haplotypes of Igf1r with four synonymous mutations in the coding sequences of IGF-1R ECD between large pigs (LP) and Bama pigs (BM) were stably expressed in the Igf1r-knockout MC3T3-E1 cells and named as MC3T3-LP cells (LP group) and MC3T3-BM cells (BM group), respectively. IGF-1R expression was lower in the BM group than in the LP group both in terms of transcription and translation levels, and IGF-1R expression inhibited cell proliferation. In addition, IGF-1R expression in the BM group promoted early-stage differentiation but delayed late-stage differentiation, which not only suppressed the expression of bone-related factors but also reduced alkaline phosphatase activity and calcium deposition. Moreover, different haplotypes of Igf1r changed the stability and conformation of the protein, further affecting the binding with IGF-1. Our data indicated that the four synonymous mutations of IGF1R ECD encoded by affect gene transcription and translation, thereby further leading to differences in the downstream pathways and functional changes of osteoblasts.