Gene-environment interaction between body mass index and transforming growth factor beta 1 (TGFβ1) gene in knee and hip osteoarthritis

Polymorphism rs143384 GDF5 reduces the risk of knee osteoarthritis development in obese individuals and increases the disease risk in non-obese population

BACKGROUND

We investigated the effect of obesity on the association of genome-wide associative studies (GWAS)-significant genes with the risk of knee osteoarthritis (KOA).

METHODS

All study participants (n = 1,100) were divided into 2 groups in terms of body mass index (BMI): BMI ≥ 30 (255 KOA patients and 167 controls) and BMI < 30 (245 KOA and 433 controls). The eight GWAS-significant KOA single nucleotide polymorphisms (SNP) of six candidate genes, such as LYPLAL1 (rs2820436, rs2820443), SBNO1 (rs1060105, rs56116847), WWP2 (rs34195470), NFAT5 (rs6499244), TGFA (rs3771501), GDF5 (rs143384), were genotyped. Logistic regression analysis (gPLINK online program) was used for SNPs associations study with the risk of developing KOA into 2 groups (BMI ≥ 30 and BMI < 30) separately. The functional effects of KOA risk loci were evaluated using in silico bioinformatic analysis.

RESULTS

Multidirectional relationships of the rs143384 GDF5 with KOA in BMI-different groups were found: This SNP was KOA protective locus among individuals with BMI ≥ 30 (OR 0.41 [95%CI 0.20-0.94] recessive model) and was disorder risk locus among individuals with BMI < 30 (OR 1.32 [95%CI 1.05-1.65] allele model, OR 1.44 [95%CI 1.10-1.86] additive model, OR 1.67 [95%CI 1.10-2.52] dominant model). Polymorphism rs143384 GDF5 manifested its regulatory effects in relation to nine genes (GDF5, CPNE1, EDEM2, ERGIC3, GDF5OS, PROCR, RBM39, RPL36P4, UQCC1) in adipose tissue, which were involved in the regulation of pathways of apoptosis of striated muscle cells.

CONCLUSIONS

In summary, the effect of obesity on the association of the rs143384 GDF5 with KOA was shown: the "protective" value of this polymorphism in the BMI ≥ 30 group and the "risk" meaning in BMI < 30 cohort.

The Role of Genetics and Epigenetic Regulation in the Pathogenesis of Osteoarthritis

Osteoarthritis (OA) is progressive disease characterised by cartilage degradation, subchondral bone remodelling and inflammation of the synovium. The disease is associated with obesity, mechanical load and age. However, multiple pro-inflammatory immune mediators regulate the expression of metalloproteinases, which take part in cartilage degradation. Furthermore, genetic factors also contribute to OA susceptibility. Recent studies have highlighted that epigenetic mechanisms may regulate the expression of OA-associated genes. This review aims to present the mechanisms of OA pathogenesis and summarise current evidence regarding the role of genetics and epigenetics in this process.

Interleukin-1 genetic polymorphisms in knee osteoarthritis: What do we know? A meta-analysis and systematic review

PURPOSE

Interleukin-1 is the main proinflammatory cytokine in osteoarthritis (OA). Several single-nucleotide polymorphisms (SNPs) within the IL-1 gene cluster (IL-1β, IL-1R1, and IL-1RN) have been determined, but their associations with knee OA remain poorly understood. The present study aimed to identify the associations between IL-1 SNPs and knee osteoarthritis.

METHODS

This meta-analysis and systematic review included all comparative studies published in the MEDLINE/PubMed, Embase, Google Scholar, and Cochrane Library databases. We performed a systematic search to identify relevant studies on the evaluation of the correlation between the IL-1 gene and knee OA published up to February 2020 that met the eligibility criteria. Nine studies on a total of 2256 knees with OA and 3527 healthy knees met the eligibility criteria. Results associated with IL-1A, IL-1B, IL-1R1, and IL-1RN SNPs were extracted and compared between knees with OA and healthy knees. Methodological quality was assessed using the Newcastle-Ottawa scale (NOS). All studies with fair or good quality were included.

RESULTS

The meta-analysis showed that the risk of knee OA is decreased by the IL-1RN*1 and IL-1RN*1/*1 genotypes and increased by the IL-1RN*2 and I-L1RN*1/*2 genotypes. The systematic review revealed only two studies associating the IL-1RN allele, none associating the IL-1B polymorphism, and only one study associating IL-1A and IL-1R1 polymorphisms with knee OA.

CONCLUSIONS

Several IL-1RN alleles and genotypes play a role in knee OA but other genetic variations in the IL-1 region were still conflicting in its association with knee OA.

Association between gene polymorphisms of TGF-β and Smad3 and susceptibility to arthritis: a meta-analysis

OBJECTIVES

This meta-analysis was performed to investigate the associations between single-nucleotide polymorphisms (SNPs) in the TGF- β and Smad3 genes and arthritis.

METHODS

A meta-analysis was performed in STATA 14.0, with publication bias and meta-regression analysis. All types of arthritis were included, and subgroup analyses were performed to interpret variations among different types of arthritis.

RESULTS

Twenty-two qualified studieswere selected to analyze the pooled accuracy, and 4 SNP sites were involved. The analysis of the TGFB1 SNP rs1800470 showed an association with arthritis in allelic (P = 0.011), homozygous (P = 0.034) and recessive (P = 0.021) genetic models. The analysis of the TGFB1 SNP rs1800471 demonstrated a close association with rheumatoid arthritis (RA) in homozygous (P = 0.000, 95%) and recessive (P = 0.008) models. The analysis of the SMAD3 SNP rs12901499 revealed a close association with osteoarthritis (OA) in the allelic (P = 0.001) model.

CONCLUSION

This research showed that genetic variants of the TGF-β pathway impact arthritis. The polymorphisms rs1800470, rs1800471 and rs12901499 were correlated with a higher prevalence of arthritis.

Role of SREBP2 gene polymorphism on knee osteoarthritis in the South Indian Hyderabad Population: A hospital based study with G595C variant

Introduction

Osteoarthritis (OA) is a multifactorial disease with genetic factors playing a crucial role, and it has been associated with a family history of obesity. G595C polymorphism in the sterol regulatory element-binding protein 2 (SREBP2) gene has demonstrated an association with knee osteoarthritis (KOA) patients. However, this polymorphism has been never explored in an Indian population. Hence, the current study aimed to examine whether G595C (rs2228314) polymorphism in SREBP2 gene was associated with KOA susceptibility in the South Indian Hyderabad population.

Methods

G595C polymorphism was genotyped with 200 KOA cases and 200 healthy controls using polymerase chain reaction-restriction fragment length polymorphism analysis.

Results

A significant association was observed between age, body mass index (BMI), and family histories in KOA cases and controls (p < 0.05). The current allele (C vs G; OR-2.8 [95%CI = 2.1-3.7]; p < 0.0001) and genotype analysis confirms the significant association with (GC + CC vs GG; OR-3.5 [95%CI = 2.3-5.3]; p < 0.0001 & GC vs GG + CC; OR-1.7 [95%CI = 1.0-2.9]; p = 0.02) KOA vs. control subjects. On stratification analysis, genotype CC and C allele were associated with KOA. Gender association failed to demonstrate positive genotype frequencies (p > 0.05). Multifactor-dimensionality reduction (MDR) analysis showed a positive association with BMI and G595C genotypes (p < 0.05); 51% of the homozygous variant CC genotypes were present in obesity subjects.

Conclusion

In conclusion, our findings suggest that G595C polymorphism in SREBP2 gene is associated with KOA in the South Indian Hyderabad population and presents scope for further investigation of the gene's function in KOA.

The role of Mean Platelet Volume/platelet count Ratio and Neutrophil to Lymphocyte Ratio on the risk of Febrile Seizure

Systemic inflammatory response has been implicated as a contributor to the onset of febrile seizures (FS). The four novel indices of the inflammatory response such as, neutrophil-to-lymphocyte ratio (NLR), mean platelet volume (MPV), platelet count (PLT) ratio and red blood cell distribution width (RDW) have been investigated in FS susceptibility and FS types (simple febrile seizure and complex febrile seizure). However, the potential role of these inflammatory markers and MPV/PLT ratio (MPR) in Chinese children with FS has yet to be fully determined. This study investigated the relevance of NLR, MPV, PLT, MPR and RDW in febrile children with and without seizures. 249 children with FS and 249 age matched controls were included in this study. NLR and MPR were calculated from complete blood cell counts prior to therapy. Differences in age, gender and these inflammatory markers between the FS group and the control group were evaluated using the chi-square test, t-test or logistic regression analysis. Receiver Operating Characteristic (ROC) curve was used to determine the optimal cut-off value of NLR and MPR for FS risk. Interactions between NLR and MPR on the additive scale were calculated by using the relative excess risk due to interaction (RERI), the proportion attributable to interaction (AP), and the synergy index (S). It has been shown that the elevated NLR and MPR levels were associated with increased risk of FS. The optimal cut-off values of NLR and MPR for FS risk were 1.13 and 0.0335 with an area under the curve (AUC) of 0.768 and 0.689, respectively. Additionally, a significant synergistic interaction between NLR and MPR was found on an additive scale. The mean levels of MPV were lower and NLR levels were higher in complex febrile seizure (CFS) than simple febrile seizure (SFS), and the differences were statistically significant. ROC analysis showed that the optimal cut-off value for NLR was 2.549 with 65.9% sensitivity and 57.5% specificity. However, no statistically significant differences were found regarding average values of MPR and RDW between CFS and SFS. In conclusion, elevated NLR and MPR add evidence to the implication of white cells subsets in FS risk, and our results confirmed that NLR is an independent, albeit limited, predictor in differentiating between CFS and SFS. Moreover, NLR and MPR may have a synergistic effect that can influence the occurrence of FS.

The c.29T>C polymorphism of the transforming growth factor beta-1 (TGFB1) gene, bone mineral density and the occurrence of low-energy fractures in patients with inflammatory bowel disease

Gastrointestinal tract conditions are frequently associated with low bone mineral density and increased risk of fractures due to osteoporosis, the latter concerning particularly inflammatory bowel disease (IBD) patients. One of the candidate genes involved in osteoporosis is the transforming growth factor beta-1 (TGFB1) whose polymorphisms may be responsible for the development of this disease. The aim of this study was to analyse the frequency of TGFB1 polymorphic variants and determine the association between the c.29T>C TGFB1 polymorphism, and bone mineral density and fractures in IBD patients. The study subjects included 198 IBD patients [100 suffering from Crohn's disease (CD) and 98 from ulcerative colitis (UC)] and 41 healthy volunteers as a control group. Densitometric bone measurements were obtained using dual energy X-ray absorptiometry. The TGFB1 genotyping was conducted using restriction fragments length polymorphism. We conducted an analysis of genotype distribution's concordance with Hardy-Weinberg equilibrium. We found statistically significant differences in lumbar spine (L2-L4) and femoral neck BMD and T-scores between CD, UC and control subgroups. The distribution of TGFB1 polymorphic variants among CD and UC patients was concordant with Hardy-Weinberg equilibrium. There were no statistically significant differences in densitometric parameters (lumbar spine and femoral neck BMD, T-score, and Z-score) between carriers of different TGFB1 polymorphisms among IBD (CD and UC) patients nor among controls. We have found no statistically significant differences in the prevalence of low-energy fractures between groups of different TGFB1 polymorphic variant carriers. The allele dose effect, recessive effect and dominant effect analysis did not show an association between low-energy fractures and the TGFB1 polymorphisms among CD and UC patients. We have not observed an association between the c.29T>C TGFB1 polymorphic variant and the bone mineral density within the cancellous and cortical bones (L2-L4 and femoral neck, respectively), or the occurrence of fractures among the IBD patients and their family members.

Interactions between polymorphisms in the 3'untranslated region of the cyclin dependent kinase 6 gene and the human papillomavirus infection, and risk of cervical precancerous lesions

The human papillomavirus (HPV) infection is essential for the development of cervical cancer and its precursor lesions. However, only certain persistently infected individuals develop cervical cancer. Cyclin-dependent kinase 6 (CDK6) is a critical regulatory cancer-associated gene in the cell cycle and in tumorigenesis. Single nucleotide polymorphisms (SNPs) in microRNA sites in the 3′-untranslated region (UTR) of target genes may result in target gene expression level changes and susceptibility to diseases, including cancer. Therefore, the aim of the present study was to determine whether SNPs in the 3′UTR of the CDK6 gene may affect susceptibility to cervical precancerous lesions in a Chinese population. Five polymorphisms in the 3′UTR of the CDK6 gene were evaluated in 164 cervical precancerous lesion cases and 296 control subjects. Differences in environmental factors between cases and controls were evaluated using the χ² test or unpaired t-test. Logistic regression was used to examine the association between the five polymorphisms and cervical precancerous lesions. The model-free multifactor dimensionality reduction (MDR) method was performed to evaluate the interaction effect of environment variables and gene polymorphisms. Interactions on the additive scale are calculated by using the relative excess risk due to interaction (RERI). After controlling for potential confounders, a significantly decreased risk of cervical precancerous lesions for the GA genotype, rs8179, and the AT genotype, rs42033 [GA vs. GA: odds ratio (OR)_adjusted=0.17, 95% confidence interval (CI), 0.05–0.57; AT vs. AA: OR_adjusted=0.18, 95% CI, 0.05–0.59, respectively] was identified. Furthermore, following MDR analysis, a significant three-locus interaction model was identified, which involved the HPV infection, the number of pregnancies and rs8179. Additionally, a significant antagonistic interaction between the HPV infection and rs8179 was identified on an additive scale. Haplotype AGTA was associated with a decreased risk of developing cervical precancerous lesions (OR_adjusted=0.21; 95% CI, 0.06–0.75). Thus, the present results indicated that the rs8179 and rs42033 polymorphisms confer genetic susceptibility to cervical precancerous lesions. Furthermore, the interaction between the rs8179 polymorphism in CDK6 and the HPV infection and haplotype AGTA may be associated with cervical precancerous lesions.

The interaction between weight and family history of total knee replacement with knee cartilage: a 10-year prospective study

OBJECTIVE

Although being overweight or obese is an important risk factor for the development of knee osteoarthritis (OA), the interplay between weight and genetic factors remains unclear. This study aimed to examine the associations between weight and knee cartilage volume/defects over 10 years in offspring having at least one parent with a total knee replacement (TKR) for primary knee OA and in controls without a knee OA family history.

METHOD

367 participants (183 offspring and 184 controls) aged from 26 to 61 years were recruited at baseline, and followed at 2 and 10 years later. T1-weighted magnetic resonance imaging (MRI) of the right knee was used to measure cartilage volume/defects at each time-point. Mixed-effects models were used with adjustment for potential confounders.

RESULTS

Study participants were middle-age adults (mean age 45 years, mean weight 77.5 kg at baseline). In multivariable analysis, increasing body weight was deleteriously associated with medial tibiofemoral cartilage volume (β = -0.28 ml, per 1 SD increase, 95% CI -0.49 to -0.07) and presence of medial tibiofemoral cartilage defects (RR = 1.27, per 1 SD increase, 95% CI 1.07 to 1.51) in offspring over 10 years. Similar associations were observed for lateral tibiofemoral cartilage volume (β = -0.19 ml, P = 0.059), and defects (RR = 1.24, P = 0.049). However, there were no statistically significant associations between weight and cartilage volume or defects in controls.

CONCLUSION

The adverse effects of increasing weight are stronger in the offspring of people with knee replacement for knee OA suggesting genetics-environment interaction with regard to overweight/obesity in the pathogenesis of knee OA particularly in the early stages.

Association between single nucleotide polymorphisms of DOT1L gene and risk of knee osteoarthritis in a Chinese Han population

To investigate associations between single nucleotide polymorphisms rs12982744 and rs12459350 in the DOT1L gene and knee osteoarthritis (OA) susceptibility in a Chinese Han population. DOT1L rs12982744 and rs12459350 polymorphisms were genotyped in patients with knee OA and age- and sex-matched OA-free controls from a Chinese Han population. A total of 605 patients with knee OA and 615 controls were enrolled in the study. GC and CC genotypes of rs12982744, and variant C, were associated with a significantly increased risk of knee OA. On stratification analysis, the association between the risk of OA and rs12982744 GC heterozygotes compared with GG homozygotes was stronger in females and those aged >65 years. In contrast, the GA and AA genotypes of rs12459350 were not significantly associated with the risk of knee OA, even after further stratification analysis according to age or sex. Our results showed that DOT1L rs12982744 G to C change and variant C genotype may contribute to knee OA risk in a Chinese Han population.

Gene-gene interactions between TGF-β/Smad3 signalling pathway polymorphisms affect susceptibility to knee osteoarthritis

OBJECTIVE

Transforming growth factor/Smad family member 3 (TGF)-β/Smad3 signalling is essential for maintaining articular cartilage. A relationship between the genetic variants of TGF-β itself, TGF-β signalling and binding molecules, and osteoarthritis (OA) has been reported. Although variants of candidate genes have become prime targets for genetic analysis, their detailed interplay has not been documented. Our goal was to establish whether single nucleotide polymorphisms (SNPs) of TGF-β1, TGF-βRI, Smad3 and tissue inhibitor of metalloproteinases 3 (TIMP3), and their interactions, are associated with knee OA.

DESIGN

We performed a case-control association study and genotyped 518 knee patients with OA and 468 healthy controls. All participants were genotyped for TGF-β1 (rs1800469C/T), TGF-βRI (rs1590A/G), Smad3 (rs12901499A/G and rs6494629T/C), and TIMP3 (rs715572G/A and rs1962223G/C) polymorphisms by polymerase chain reaction-restriction fragment length polymorphism analysis. Multifactor dimensionality reduction (MDR) was used to identify gene-gene interactions.

RESULTS

Significant associations were observed for TIMP3 rs715572G/A polymorphisms in knee patients with OA and healthy individuals. The GA heterozygote in TIMP3 (rs715572G/A) was significantly associated with OA (p=0.007). Patient stratification using the Kellgren-Lawrence grading scale showed significant differences in TIMP3 rs715572G/A genotypes between grade 4 knee OA and controls. By MDR analysis, a two-locus model (Smad3 rs6494629T/C and TIMP3 rs715572G/A) of gene-gene interaction was the best for predicting knee OA risk, and its maximum testing accuracy was 57.55% and maximum cross-validation consistency was 10/10.

CONCLUSIONS

TIMP3 rs715572G/A is a candidate protective gene for severe knee OA. Gene-gene interactions between Smad3 rs6494629T/C and TIMP3 rs715572G/A polymorphisms may play more important protective roles in knee OA.

A single nucleotide polymorphism in the TGF-β1 gene (rs1982073 C>T) may contribute to increased risks of bone fracture, osteoporosis, and osteoarthritis: a meta-analysis

Genetic factors have been shown to be of great importance for the pathogenesis of bone diseases, such as fracture, osteoporosis (OP), and osteoarthritis (OA). However, published studies on the correlations of transforming growth factor-β1 (TGF-β1) gene polymorphisms with bone diseases have been hampered by small sample sizes or inconclusive findings. We hence aimed at examining the relationships between a single nucleotide polymorphism in the TGF-β1 gene (rs1982073 C>T) with bone fracture, OP, and OA risks in this meta-analysis. A systematic electronic search of literature was conducted to identify all published studies in English or Chinese on the association between the TGF-β1 gene and fracture, OP, or OA risks. Data were abstracted independently by two reviewers. To investigate the strength of this relationship, crude odds ratios with 95 % confidence intervals were used. An updated meta-analysis based on nine independent case-control studies were chosen (patients with fracture, OP, or OA = 1569; healthy controls = 1638). Results identified a higher frequency of rs1982073 C>T in patients with fracture, OP, or OA than in healthy controls. Ethnicity and genotyping method-stratified analysis under both models implied that the rs1982073 C>T polymorphism was positively correlated with the risk of fracture, OP, and OA among Asians under detection via the non-PCR-RFLP method. Disease-stratified results yielded that rs1982073 C>T may increase the risk of fracture, OP, and OA under the allele model, but was only significantly related to OP under the dominant model. According to the sample size-stratified analysis, subjects with the rs1982073 C>T polymorphism in the allele model were more likely to develop the three bone diseases in both the small and large sample size groups, and only in the large sample size under the dominant model. Our findings show that TGF-β1 rs1982073 C>T has a modest effect in increasing susceptibility to bone fracture, OP, and OA.