Polymorphisms in Wnt signaling pathway genes are associated with peak bone mineral density, lean mass, and fat mass in Chinese male nuclear families

Peak Bone Mass Formation: Modern View of the Problem

Peak bone mass is the amount of bone tissue that is formed when a stable skeletal state is achieved at a young age. To date, there are no established peak bone mass standards nor clear data on the age at which peak bone mass occurs. At the same time, the level of peak bone mass at a young age is an important predictor of the onset of primary osteoporosis. The purpose of this review is to analyze the results of studies of levels of peak bone mass in general, the age of its onset, as well as factors influencing its formation. Factors such as hormonal levels, body composition, physical activity, nutrition, heredity, smoking, lifestyle, prenatal predictors, intestinal microbiota, and vitamin and micronutrient status were considered, and a comprehensive scheme of the influence of these factors on the level of peak bone mass was created. Determining the standards and timing of the formation of peak bone mass, and the factors affecting it, will help in the development of measures to prevent its shortage and the consequent prevention of osteoporosis and concomitant diseases.

The role of WNT10B in physiology and disease: A 10-year update

WNT10B, a member of the WNT family of secreted glycoproteins, activates the WNT/β-catenin signaling cascade to control proliferation, stemness, pluripotency, and cell fate decisions. WNT10B plays roles in many tissues, including bone, adipocytes, skin, hair, muscle, placenta, and the immune system. Aberrant WNT10B signaling leads to several diseases, such as osteoporosis, obesity, split-hand/foot malformation (SHFM), fibrosis, dental anomalies, and cancer. We reviewed WNT10B a decade ago, and here we provide a comprehensive update to the field. Novel research on WNT10B has expanded to many more tissues and diseases. WNT10B polymorphisms and mutations correlate with many phenotypes, including bone mineral density, obesity, pig litter size, dog elbow dysplasia, and cow body size. In addition, the field has focused on the regulation of WNT10B using upstream mediators, such as microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). We also discussed the therapeutic implications of WNT10B regulation. In summary, research conducted during 2012-2022 revealed several new, diverse functions in the role of WNT10B in physiology and disease.

WNT4 Balances Development vs Disease in Gynecologic Tissues and Women's Health

The WNT family of proteins is crucial in numerous developmental pathways and tissue homeostasis. WNT4, in particular, is uniquely implicated in the development of the female phenotype in the fetus, and in the maintenance of müllerian and reproductive tissues. WNT4 dysfunction or dysregulation can drive sex-reversal syndromes, highlighting the key role of WNT4 in sex determination. WNT4 is also critical in gynecologic pathologies later in life, including several cancers, uterine fibroids, endometriosis, and infertility. The role of WNT4 in normal decidualization, implantation, and gestation is being increasingly appreciated, while aberrant activation of WNT4 signaling is being linked both to gynecologic and breast cancers. Notably, single-nucleotide polymorphisms (SNPs) at the WNT4 gene locus are strongly associated with these pathologies and may functionally link estrogen and estrogen receptor signaling to upregulation and activation of WNT4 signaling. Importantly, in each of these developmental and disease states, WNT4 gene expression and downstream WNT4 signaling are regulated and executed by myriad tissue-specific pathways. Here, we review the roles of WNT4 in women's health with a focus on sex development, and gynecologic and breast pathologies, and our understanding of how WNT4 signaling is controlled in these contexts. Defining WNT4 functions provides a unique opportunity to link sex-specific signaling pathways to women's health and disease.

WNT5B in Physiology and Disease

WNT5B, a member of the WNT family of proteins that is closely related to WNT5A, is required for cell migration, cell proliferation, or cell differentiation in many cell types. WNT5B signals through the non-canonical β-catenin-independent signaling pathway and often functions as an antagonist of canonical WNT signaling. Although WNT5B has a high amino acid identity with WNT5A and is often assumed to have similar activities, WNT5B often exhibits unique expression patterns and functions. Here, we describe the distinct effects and mechanisms of WNT5B on development, bone, adipose tissue, cardiac tissue, the nervous system, the mammary gland, the lung and hematopoietic cells, compared to WNT5A. We also highlight aberrances in non-canonical WNT5B signaling contributing to diseases such as osteoarthritis, osteoporosis, obesity, type 2 diabetes mellitus, neuropathology, and chronic diseases associated with aging, as well as various cancers.

The rs1634330 Polymorphisms in the SOST Gene Are Associated with Body Composition in Chinese Nuclear Families with Male Offspring

OBJECTIVE

The purpose of this study was to explore the effect of the SOST gene polymorphisms on body composition in Chinese nuclear families with male offspring.

METHODS

1,016 individuals were recruited from 335 Chinese nuclear families with male offspring. The nuclear families consist of at least one male offspring aged 18 to 44. We genotyped the 10 tagged single-nucleotide polymorphisms (SNPs) in SOST gene (rs7220711, rs865429, rs851057, rs1708635, rs2023794, rs1234612, rs74252774, rs1634330, rs851058, and rs1513670) in all the above people. We used dual-energy X-ray absorptiometry to measure the composition of the human body. The quantitative transmission disequilibrium test (QTDT) was used to analyze the associations of the SNPs with the body composition.

RESULTS

QTDT analysis showed that rs1634330 was significantly associated with trunk LM (P < 0.05). However, haplotypes were not found to be significantly associated with the body composition in the within-family association. The 1000 permutations were consistent with these within-family association results.

CONCLUSIONS

Our results showed that the genetic variation in the SOST gene may contribute to variations in the body composition of Chinese male offspring.

Parallel repulsive logic regression with biological adjacency

Logic regression, an extension of generalized linear models with Boolean combinations of binary variables as predictors, is a useful tool in exploring interactions among single-nucleotide polymorphisms (SNPs) in genome-wide association studies. However, since the search space defined by all possible combinations of SNPs, their complements, and logical operators in Boolean expressions can be exceedingly large in such studies, objective function optimization is slow and likely to be trapped in many local solutions, resulting in model over-fitting. We introduce a new search algorithm, parallel repulsive logic regression (PRLR), to efficiently estimate parameters of a logic regression to find a best model within the large space of SNP interactions by incorporating: (i) relevant biological adjacency matrix between SNPs to define similarity of estimation paths or trees, which are derived from physical SNP positions on chromosomes and/or memberships in biological gene pathways; and (ii) two repulsive forces to counter the similarity between and within estimation paths considered in parallel, which are introduced as penalty terms in the objective function. We compare our method's performance for identifying biologically-meaningful SNP interactions through simulations and with real genetic-epidemiological data. PRLR's detection-accuracy measures outperform existing approaches, especially in terms of positive predictive value and sensitivity for detecting SNP-SNP interactions.

Association between LGR4 polymorphisms and peak bone mineral density and body composition

INTRODUCTION

Leucine-rich repeat-containing G protein-coupled receptor 4 (LGR4) could affect differentiation of osteoblasts and bone mass through potentiating Wnt/β-catenin signaling. LGR4 is also relevant to glycolipid metabolism. The present study aims to explore the relationship between genetic variations in LGR4 gene and peak bone mineral density (peak BMD) and body composition phenotypes in Chinese nuclear families.

MATERIALS AND METHODS

22 single-nucleotide polymorphisms (SNPs) were selected and five blocks were constructed in LGR4. Body composition (lean mass and fat mass) and peak BMD were measured by dual-energy X-ray absorptiometry (DXA). Quantitative transmission disequilibrium test (QTDT) analysis was used to explore the relationship between LGR4 genotypes and the mentioned phenotypes.

RESULTS

For QTDT analysis after 1000 permutations, significant within-family associations were observed between rs11029986 and total fat mass (TFM) and percentage of TFM (PFM) (P = 0.014 and 0.011, respectively), rs12787344, rs4128868, rs4923445, and rs7936621 and body mass index (BMI) (P = 0.008, 0.003, 0.046, and 0.003, respectively), rs11029986 and total hip BMD (P = 0.026), and rs12796247, rs2219783, and lumbar spine BMD (P = 0.013 and 0.027, respectively). Haplotypes GCGT and AAGC (both in block 3) were observed in significant within-family association with BMI (P = 0.003 and 0.002, respectively).

CONCLUSION

It is the first family-based association analysis to explore and demonstrate significant associations between LGR4 genotypes and variations of peak BMD and body composition in young Chinese men. The results are consistent with the findings that recent studies revealed, and confirm the critical relationship between LGR4 gene and both BMD and body composition.

The rs2302685 polymorphism in the LRP6 gene is associated with bone mineral density and body composition in Iranian children

BACKGROUND

Some 60-80% of the variability in bone mineral density (BMD) is determined by genetic factors. In the present study, we investigated the impact of the rs2302685 polymorphism of LRP6 on BMD and body composition in Iranian children.

METHODS

In total, 200 children (101 boys and 99 girls) were enrolled in the study. Body composition and BMD were computed using the Hologic DXA System (Hologic, Marlborough, MA, USA). The single nucleotide polymorphism of LRP6 rs2302685 (V1062I) was determined using a polymerase chain reaction/restriction fragment length polymorphism. A generalized linear model was performed to find the association between LRP6 polymorphisms, BMD and body composition in two adjusted models.

RESULTS

In model 1, a significant difference was found between LRP6 (rs2302685) polymorphism, trochanteric BMD (p = 0.007), intertrochanteric BMD (p = 0.007), total fat (p = 0.001), total fat (%) (p = 0.034), total lean mass (p = 0.031), total Lean + BMC (p = 0.036) and total mass (p = 0.001). In model 2, LRP6 (rs2302685) polymorphisms showed a significant effect on the trochanteric BMD (p = 0.005), intertrochanteric BMD (p = 0.005), total fat (p = 0.001), total fat (%) (p = 0.013) and total mass (p = 0.01). Total fat, total fat (%) and total body mass were higher in subjects with the CC genotype compared to the TT/CT genotype, whereas total lean mass and total Lean + BMC were higher in the TT/CT genotype.

CONCLUSIONS

The present study shows that the LRP6 polymorphism may be associated with body composition and BMD in Iranian children.

Wnt family member 4 (WNT4) and WNT3A activate cell-autonomous Wnt signaling independent of porcupine O-acyltransferase or Wnt secretion

Porcupine O-acyltransferase (PORCN) is considered essential for Wnt secretion and signaling. However, we observed that PORCN inhibition does not phenocopy the effects of WNT4 knockdown in WNT4-dependent breast cancer cells. This suggests a unique relationship between PORCN and WNT4 signaling. To examine the role of PORCN in WNT4 signaling, here we overexpressed WNT4 or WNT3A in breast cancer, ovarian cancer, and fibrosarcoma cell lines. Conditioned media from these lines and co-culture systems were used to assess the dependence of Wnt secretion and activity on the critical Wnt secretion proteins PORCN and Wnt ligand secretion (WLS) mediator. We observed that WLS is universally required for Wnt secretion and paracrine signaling. In contrast, the dependence of WNT3A secretion and activity on PORCN varied across the cell lines, and WNT4 secretion was PORCN-independent in all models. Surprisingly, WNT4 did not exhibit paracrine activity in any tested context. Absent the expected paracrine activity of secreted WNT4, we identified cell-autonomous Wnt signaling activation by WNT4 and WNT3A, independent of PORCN or Wnt secretion. The PORCN-independent, cell-autonomous Wnt signaling demonstrated here may be critical in WNT4-driven cellular contexts or in those that are considered to have dysfunctional Wnt signaling.

Regulatory Fluctuation of WNT16 Gene Expression Is Associated with Human Gastric Adenocarcinoma

INTRODUCTION

Gastric cancer is one of the most serious and lethal kinds of cancer in the world. It is a multi-step, multi-factor, and elaborated process that is associated to gene abnormal expression. This study intended to investigate the WNT16 gene's expression in human gastric tumor and the margin tissues of the stomach (normal tissues).

METHODS

Correspondingly, 40 samples (20 tumoral tissues and 20 non tumoral or margins tissues) were investigated in Imam Khomeini Hospital in Sari City, Mazandaran Province, Iran. In this way, real-time PCR, Taqman assay was employed to evaluate the upregulation and downregulation of this gene in both tissues in triplicate form. The GAPDH gene was selected as housekeeping gene.

RESULTS

Conspicuously, the results have shown a remarkable modification in tumoral tissues, and the gene expression increased significantly in tumoral tissue.

CONCLUSIONS

Conclusively, the upregulation of WNTt16 gene expression in tumoral tissues was impressive and the P value was 0.005 and the SE range was 0.064-142.154.

Effect of Anacardic Acid against Thiram Induced Tibial Dyschondroplasia in Chickens via Regulation of Wnt4 Expression

Simple Summary

This study evaluated the ameliorating effect of anacardic acid (AA) in tibial dyschondroplasia (TD) chickens. Our results showed that AA can increase the feed conversion ratio, improve the weight, length and width of the tibia. AA administration restored the antioxidant parameters significantly (p < 0.05). The gene expression analysis revealed a decrease in wingless-type member 4 (Wnt4) expressions in TD chickens as compared to the control group, while AA treatment up-regulated the Wnt4 expression. The present study demonstrates that the AA plays an important role to prevent the lameness and restore the size of the tibial growth plate of chickens by regulating the expression of Wnt4.

Abstract

Tibial dyschondroplasia (TD) is a tibia bone problem in broilers. Anacardic acid (AA) is a traditional Chinese medicine, which is commonly used to treat arthritis in human. The purpose of the present study is to investigate the effect of AA against TD. A total of 300 day-old poultry birds were equally divided and distributed into three different groups: Control, TD and AA groups. The results showed that the feed conversion ratio was significantly lower in the TD group than control chickens. The tibia bone parameters including weight, length and width were of low quality in TD chickens, while the width of the tibial growth plate was enlarged remarkably. Whereas, in the AA treatment group, the tibia bone parameters showed improvement and tend to return to normal. The antioxidant parameters level of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), total and antioxidant capacity (T-AOC) was significantly decreased, while malondialdehyde (MDA) level was increased significantly in TD affected chickens. AA administration restored the antioxidant parameters significantly. The gene expression revealed a decrease in Wnt4 expression in TD chickens as compared to control chickens, while AA treatment up-regulated the Wnt4 expression. The present study demonstrates that the AA plays an important role to prevent the lameness and restore the size of tibial growth plate of chickens by regulating the expression of Wnt4.

A specific haplotype in potential miRNAs binding sites of secreted frizzled-related protein 1 (SFRP1) is associated with BMD variation in osteoporosis

PURPOSE

Osteoporosis is an important multifactorial disease which is largely influenced by Wnt signaling pathway. Considering regulatory single nucleotide polymorphisms in Wnt signaling pathway may pave the road of understanding the genetic basis of predisposition to osteoporosis. The aim of this study was to determine the possible association between variants of SFRP1 and WNT5b, and osteoporosis incidence risk.

METHODS

The study population comprised 186 osteoporotic patients and 118 normal subjects from Amirkola Health and Ageing Project. rs1127379 (c.1406A>G) and rs3242 (c.3132C>T) variants in 3'UTR of SFRP1 gene, and rs3803164 (c.236C>T) in 3'UTR and rs735890 (c.622-536A>G) in intron 4 of WNT5b gene were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Regression analyses were used to calculate the association of genotype frequencies with bone mineral density (BMD) and bone mineral content (BMC) values of participants. Bioinformatics algorithms were used to detect the effect of each SNP on the secondary structure of mRNA, and predict putative 3'UTR microRNA target sites and splicing sites changes by related SNPs.

RESULTS

WNT5b rs735890 was associated with lumbar spine BMD, BMC, and femoral neck BMC (P = 0.035, P = 0.007, and P = 0.038, respectively). WNT5b rs3803164, and SFRP1 rs3242 were significantly associated with lumbar spine BMD (P = 0.028 and P = 0.030, respectively). SFRP1 rs1127379 was associated with lumbar spine BMD in the male gender. Haplotype analysis showed a significant association of SFRP1 c.[1406A; 3132C] haplotype with lumbar spine BMD, and BMC (P = 0.019 and P = 0.030, respectively), and SFRP1 c.[1406G; 3132C] haplotype with lumbar spine BMC (P = 0.045). In silico analyses revealed that the G allele of SFRP1 rs1127379, and WNT5b rs3803164 appear as more possible target sites for many miRNAs.

CONCLUSIONS

This study is the first evidence of the association of WNT5b rs735890, and c.[1406A; 3132C] and c.[1406G; 3132C] haplotypes of SFRP1 with BMD variation in osteoporosis, probably by altering microRNA target sites, in elderly persons.

Bone morphogenetic protein 9 stimulates callus formation in osteoporotic rats during fracture healing

Fracture healing involves the coordinated actions of multiple cytokines. Bone morphogenetic protein 9 (BMP9) is an important factor in bone formation. The present study aimed to investigate the osteogenic potential of bone marrow stem cells (BMSCs) in response to adenoviral (Ad)BMP9, and the early fracture repair properties of AdBMP9 in surgically-created fractures in osteoporotic rats. Alkaline phosphatase (ALP) activity was assayed and matrix mineralization was examined by Alizarin Red S staining. mRNA and protein expression levels of BMP9, runt-related transcription factor 2 (RUNX2) and type 1 collagen (COL-1) were detected in vitro and in vivo. Femoral bone mineral density was assessed for osteoporosis in ovariectomized rats. An open femora fracture was subsequently created, and gelatin sponges containing AdBMP9 were implanted. The femora were harvested for radiographical, micro-computed tomography, biomechanical and histological analysis 4 weeks later. BMP9 successfully increased ALP activity and induced mineralized nodule formation in BMSCs. BMP9 in gelatin sponges demonstrated marked effects on microstructural parameters and the biomechanical strength of bone callus. In addition, it upregulated the expression levels of RUNX2 and COL-1. AdBMP9 in gelatin sponges significantly mediated callus formation, and increased bone mass and strength in osteoporotic rats with femora fractures. The results of the present study suggested that BMP9 enhanced callus formation and maintained early mechanical stability during fracture healing in osteoporotic rats, implicating it as a potential novel therapeutic target for fracture healing.

Genetic Screening of WNT4 and WNT5B in Two Populations with Deviating Bone Mineral Densities

A role for WNT4 and WNT5B in bone metabolism was indicated by genome-wide association studies (GWAS) and a Wnt4 knockout mouse model. The aim of this study was therefore to replicate and further investigate the causality between genetic variation in WNT4 and WNT5B and deviating bone mineral density (BMD) values. A WNT4 and WNT5B mutation screening was performed in patients with craniotubular hyperostosis using Sanger sequencing. Here, no putative causal mutations were detected. Moreover, a high and low BMD cohort was selected from the Odense Androgen Study population for re-sequencing. In WNT4 we detected four variants (three rare, one common), while in WNT5B we detected five variants (two rare, three common). For the common variants, no significant difference in genotype frequencies between the high and low BMD cohorts was observed. The SNPs associated with the GWAS were genotyped in these cohorts, but again no significant difference in genotype frequencies was observed. Despite the findings of the GWAS, we were not able to replicate or further verify the genetic association of polymorphisms in WNT4 and WNT5B with BMD. In order to do so, the intronic regions of both genes could be investigated more thoroughly in more extended populations (or extremes) with greater power. Future genetic and functional studies toward adjacent genes of WNT4 and WNT5B can also be interesting to figure out whether the signal from GWAS could possibly be attributed to genetic variation in these genes.