Vitamin D receptor gene polymorphisms and risk of osteoarthritis: A meta-analysis

Evaluating the potential of Vitamin D and curcumin to alleviate inflammation and mitigate the progression of osteoarthritis through their effects on human chondrocytes: A proof-of-concept investigation

Osteoarthritis (OA) is a chronic degenerative joint disorder primarily affecting the elderly, characterized by a prominent inflammatory component. The long-term side effects associated with current therapeutic approaches necessitate the development of safer and more efficacious alternatives. Nutraceuticals, such as Vitamin D and curcumin, present promising therapeutic potentials due to their safety, efficacy, and cost-effectiveness. In this study, we utilized a proinflammatory human chondrocyte model of OA to assess the anti-inflammatory properties of Vitamin D and curcumin, with a particular focus on the Protease-Activated Receptor-2 (PAR-2) mediated inflammatory pathway. Employing a robust siRNA approach, we effectively modulated the expression of PAR-2 to understand its role in the inflammatory process. Our results reveal that both Vitamin D and curcumin attenuate the expression of PAR-2, leading to a reduction in the downstream proinflammatory cytokines, such as Tumor Necrosis Factor-alpha (TNF-α), Interleukin 6 (IL-6), and Interleukin 8 (IL-8), implicated in the OA pathogenesis. Concurrently, these compounds suppressed the expression of Receptor Activator of Nuclear Factor kappa-Β Ligand (RANKL) and its receptor RANK, which are associated with PAR-2 mediated TNF-α stimulation. Additionally, Vitamin D and curcumin downregulated the expression of Interferon gamma (IFN-γ), known to elevate RANKL levels, underscoring their potential therapeutic implications in OA. This study, for the first time, provides evidence of the mitigating effect of Vitamin D and curcumin on PAR-2 mediated inflammation, employing an siRNA approach in OA. Thus, our findings pave the way for future research and the development of novel, safer, and more effective therapeutic strategies for managing OA.

A cross-sectional study to find association of VDR gene polymorphism with non-syndromic congenital ichthyosis and with vitamin D deficiency

Though development of vitamin D deficiency and rickets in patients with congenital ichthyosis (CI) have recently been observed, yet exact cause of such association is not properly understood. To evaluate association between Vitamin D Receptor (VDR) polymorphism and CI, and to identify risk factors responsible for development of vitamin D deficiency in ichthyosis. In this cross-sectional study, detailed history of patients and controls was noted and certain biochemical investigations were made. Immunohistochemical staining of skin tissue was done for VDR expression in epidermal and dermal region of ichthyosis patients. VDR polymorphism was assessed in all participants. Ninety-six subjects, were recruited. Mean serum vitamin D was significantly lower among ichthyosis patients. Cdx-2 polymorphism was found to be significantly associated with ichthyosis (p = 0.009). Within the diseased group, Fok-1 (p = 0.035), age (p = 0.020) and alkaline phosphatase (ALP) (p = 0.007) emerged as factors which might be associated with vitamin D deficiency. Cdx2 polymorphism was significantly associated with CI patients. Also, association of Fok-1 polymorphism along with age and raised serum ALP levels emerged as potential factors for determining CI-related vitamin D deficiency.

Association between genetic polymorphisms and osteoarthritis development. Overview of systematic reviews

OBJECTIVE

To identify, critically evaluate and synthesize the evidence obtained from systematic reviews on the association between genetic polymorphisms and osteoarthritis (OA) development.

METHODS

Considering gene polymorphisms associated with OA susceptibility (risk or protection), a comprehensive search was conducted in the following databases, without date or language restrictions: MEDLINE, via Pubmed; Embase, via Elsevier; Cochrane Database of Systematic Reviews, via Wiley; Biblioteca Virtual em Saúde. Gray literature was also searched through the OpenGrey database. The AMSTAR-2 (Assessing the Methodological Quality of Systematic Reviews) was used to assess the methodological quality of the included systematic reviews.

RESULTS

We included 14 systematic reviews of case-control studies comparing individuals with a radiographic diagnosis of all OA types and healthy controls, all submitted to the genetic examination of different polymorphisms in candidate genes. Meta-analyses showed a protective effect against knee and hand OA associated with GDF-5 gene (odds ratio [OR] 0.90, 95% confidence interval (CI) 0.85-0.95), and knee OA with ESRα gene (OR 0.63, 95% CI 1.26-1.97). SMAD3 gene was associated with knee and hip OA risk (OR 1.21. 95% CI 1.07-1.38) and MMP-1 gene was associated with temporomandibular OA (OR 1.58. 95% CI 1.26-1.97).

CONCLUSION

Based on low-quality to critically-low-quality systematic reviews, some gene polymorphisms seem to be associated with risk or protection for OA. Further high-quality studies are needed to validate these hypotheses, contribute to disease understanding, and possibly help the decision-making related to early diagnosis and treatment options for OA. PROSPERO register CRD42021234231.

Vitamin D receptor gene polymorphisms and osteoarthritis: a meta-analysis

OBJECTIVE

To investigate the association of vitamin D receptor (VDR) gene polymorphisms with OA susceptibility.

METHODS

Meta-analyses were performed using allelic contrast, contrast of homozygotes, and recessive and dominant models to clarify the association between OA and VDR ApaI, BsmI, TaqI and FokI polymorphisms. Odds ratio (OR) and the corresponding 95% CI were obtained, and subgroup analyses were performed based on the ethnicity and OA sites.

RESULTS

A total of 18 studies with 2983 OA patients and 4177 controls were included in this meta-analysis. There were statistically significant associations in the spine between OA susceptibility and the VDR BsmI (B vs b: OR = 1.25, 95% CI: 1.03, 1.53, P = 0.026; BB vs bb: OR = 1.56, 95% CI: 1.02, 2.37, P = 0.038) and TaqI (T vs t: OR = 0.73, 95% CI: 0.54, 0.99, P = 0.044; TT vs Tt + tt: OR = 0.63, 95% CI: 0.42, 0.95, P = 0.028) polymorphisms, but not for the other polymorphisms. A statistically significant association was found between the VDR FokI polymorphism and OA susceptibility in the knee in the recessive model contrast (FF vs Ff + ff: OR = 0.63, 95% CI: 0.42, 0.95, P = 0.028), but this result was only pooled from one study. However, no significant associations were found between the VDR ApaI polymorphism and OA. Besides, ethnic stratification also indicated that there was no significant association between VDR gene polymorphism and OA in Caucasians or Asians.

CONCLUSION

Our meta-analysis suggests that the VDR BsmI and TaqI polymorphisms are associated with OA susceptibility in the spine. However, the VDR ApaI polymorphism is not a significant genetic risk factor for OA.

Association of the Risk of Osteoarthritis and Hypertension in the Korean Adult Population Aged 40-59 in Pre- and Postmenopausal Women: Using Korea National Health and Nutrition Examination Survey 2012-2016 Data

Purpose

Previous studies reported the relation of osteoarthritis (OA) and hypertension (HTN) mostly in postmenopausal women. This study aimed to identify the association between OA and HTN in pre- and postmenopausal women.

Methods

We used data of 4,627 middle-aged (40–59 years) women from the Korea National Health and Nutrition Examination Survey (KNHANES) from 2012 to 2016. Chi-square and t-test compared the characteristics of the participants. Binomial logistic regression was used to identify an association between OA and HTN under controlling covariates such as age, tobacco smoking, alcohol consumption, and obesity.

Results

There were 1,859 participants with non-OA and menopause, 104 with OA and nonmenopause, and 375 with OA and menopause, respectively. The number of women with OA and HTN was 129. OA was significantly associated with HTN diagnosis in postmenopausal women under controlling covariates (odds ratio: 1.408, 95% CI: 1.092–1.815, p=0.008). However, this relationship was weakened in premenopausal women (odds ratio: 1.651, 95% CI: 0.950–2.869, p=0.075).

Conclusion

In conclusion, women with HTN showed a distinct association with OA than the normotensives, and this relationship was more apparent among postmenopausal women. Further research is needed for a preventive approach.

Vitamin D receptor gene polymorphisms (Apa1 and Taq1) in temporomandibular joint internal derangement/osteoarthritis in a group of Turkish patients

Genetic variations might play a role in susceptibility to temporomandibular joint internal derangement (TMJ-ID) and osteoarthritis of the joint (TMJOA). Vitamin D receptor (VDR) polymorphisms have been shown to be associated with disc degeneration-linked pathologies, particularly osteoarthritis (OA). The aim of this study was to evaluate whether VDR polymorphisms present susceptibility to TMJ-ID/TMJOA. The study included 49 unrelated TMJ-ID patients with OA (31.7 ± 7.9) that were grouped and evaluated as having anterior disk displacement with reduction (ADDwR, n = 24) (31.58 ± 8.25) and without reduction (ADDwoR, n = 25) (31.8 ± 7.53) and 70 healthy controls (28.22 ± 5.9). DNA was extracted from blood samples using the standard proteinase K/phenol-chloroform method. Apa1 and Taq1 polymorphisms were investigated using a polymerase chain reaction-based restriction fragment length polymorphism assay. When TMJ-ID patients, ADDwR cases and ADDwoR cases versus healthy controls were compared, Apa1 Aa genotype compared to AA genotype had odds ratios of 1.65, 1.79 and 1.64 respectively (p > 0.05). In TMJ-ID women versus healthy women Aa genotype had 2.06 fold (p = 0.15) odds compared to AA genotype. Taq1 results showed that in TMJ-ID patients and ADDwoR cases the Tt genotype had odds ratios of 0.63 and 0.44 fold (p > 0.05) respectively. In TMJ-ID women the Tt and tt genotypes had odds ratios of 0.53 and 0.73 (p > 0.05). Combined VDR genotypes revealed that AATT had a 3.3 fold (p = 1.21) odds ratio while AATt had a 2.0 fold odds ratio (p = 0.29) (OR 0.59, 95% CI 0.23-1.49, p = 0.26) compared to AaTt. Although our results do not confirm susceptibility of VDR polymorphisms to TMJ-ID/TMJOA ,this relation needs to be further evaluated in a large cohort study.

Association between hypertension and risk of knee osteoarthritis: A meta-analysis of observational studies

Evidence from observational studies shows that hypertension may be a risk factor for knee osteoarthritis (OA). However, the relationship between hypertension and knee OA risk remains controversial. This study aimed to quantitatively assess the relationship between hypertension and risk of knee OA.Three electronic databases (PubMed, Embase, and Cochrane Library) were searched up to July 25, 2016. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were extracted from the included observational studies. Publication bias, heterogeneity test, and subgroup analyses were performed.Eight studies including 2 cohort studies and 6 cross-sectional studies with 9762 participants were finally included in this meta-analysis. The results showed that hypertension was significantly associated with higher radiographic knee OA and symptomatic knee OA risks of 2.01 (95% CI, 1.28-3.15, I = 90.2%, P for heterogeneity <.001) and 1.49 (95% CI, 1.26-1.77, I = 0%, P for heterogeneity <.412), respectively. No publication bias was detected. The subgroup analysis showed that the study design did not influence the results (radiographic knee OA: OR = 1.42, 95% CI, 1.19-1.71 for cross-sectional studies and OR = 2.17, 95% CI, 1.30-3.63 for cohort studies; and symptomatic knee OA: OR = 1.85, 95% CI, 1.10-3.13) for cross-sectional studies and OR = 2.74, 95% CI, 1.81-4.16 for cohort studies).This meta-analysis showed that there was a significant relationship between hypertension and knee OA (both radiographic and symptomatic). However, further original studies are needed that use a better design.

Ginsenoside Rb1 inhibits matrix metalloproteinase 13 through down-regulating Notch signaling pathway in osteoarthritis

Mounting evidence suggests that an excess of matrix metalloproteinase-13 (MMP-13) plays an important role in the breakdown of extracellular matrix in osteoarthritis (OA). Here, the effects of ginsenoside Rb1 (GRb1) on the expression of MMP-13 in IL-1β-induced SW 1353 chondrosarcoma cells and an experimental rat model of OA induced by anterior cruciate ligament transection (ACLT) were investigated. SW1353 chondrosarcoma cells were pretreated with or without GRb1 and Notch signaling pathway inhibitor, DAPT, then were stimulated with IL-1β. In rats, experimental OA was induced by ACLT. These rats then received intra-articular injections of vehicle, an inhibitor of γ-secretase, DAPT, and/or GRb1. Expression of MMP-13, collagen type II (CII), Notch1, and jagged 1 (JAG1) were verified by western blotting and immunohistochemistry. In addition, levels of MMP-13 mRNA were detected using quantitative real-time PCR. In histological analyses, treatment with DAPT reduced the number of cartilage lesions present and the expressions of MMP-13, CII, Notch1, and JAG1. In addition, treatment with GRb1 was associated with lower levels of Notch1 and JAG1 in both IL-1β-induced SW1353 chondrosarcoma cells and in the rat OA model. Furthermore, the suppressive effect of GRb1 on MMP-13 was greater than that exhibited by the signaling pathway inhibitor. In conclusion, GRb1 inhibits MMP-13 through down-regulating Notch signaling pathway in OA.

Osteoarthritis year in review 2014: genetics and genomics

Recent developments in genetics/genomics of osteoarthritis (OA) are discussed to improve our understanding of OA pathophysiology. The discovery of a novel variant near the NCOA3 (nuclear receptor coactivator 3) gene associated with hip OA and the regulation of GDF5 gene by four transcription factors via the OA susceptibility locus rs143383 are among important findings in OA genetics. Several microarray-based gene expression studies were published for different tissues of the joint. In OA synovium elevation of collagens and cross-linking enzymes (COL1A1, COL5A1, PLOD2, LOX and TIMP1) responsive to TGF-β was found as well as differential expression pattern between different areas of the osteoarthritic synovial membrane. In OA peripheral blood the role of apoptotic genes was highlighted, while whole genome expression profiling in OA subchondral bone and cartilage revealed common genes in cartilage and bone to be involved in OA development. In epigenetics, several microRNAs (miRNAs) were found to regulate genes' expression in chondrocytes, among which miR-125, miR-127b miR-21, miR-148a and their use as potential drug targets was highlighted. Future studies must focus on the integration of genetics, genomics and epigenetics for the identification of signaling pathways and regulatory networks responsible for OA development.