Effect of vitamin D3 on prostaglandin E2 synthesis in osteoblast-like cells

Vitamin Effects in Primary Dysmenorrhea

BACKGROUND

Primary dysmenorrhea is considered to be one of the most common gynecological complaints, affecting women's daily activities and social life. The severity of dysmenorrhea varies among women, and its management is of high importance for them. Given that non-steroidal anti-inflammatory drugs (NSAIDs), the established treatment for dysmenorrhea, are associated with many adverse events, alternative therapeutic options are under evaluation. Emerging evidence correlates management of dysmenorrhea with micronutrients, especially vitamins.

PURPOSE

The aim of this narrative review is to highlight and provide evidence of the potential benefits of vitamins for the management of dysmenorrhea.

METHODS

The articles were searched on PubMed, Scopus and Google Scholar. The searching process was based on keywords, such as "primary dysmenorrhea", "vitamins", "supplementation", "vitamin D", "vitamin E" and others. Our search focused on data derived from clinical trials, published only during the last decade (older articles were excluded).

RESULTS

In this review, 13 clinical trials were investigated. Most of them supported the anti-inflammatory, antioxidant and analgesic properties of vitamins. Particularly, vitamins D and E revealed a desirable effect on dysmenorrhea relief Conclusion: Despite the scarcity and heterogeneity of related research, the studies indicate a role of vitamins for the management of primary dysmenorrhea, proposing that they should be considered as alternative therapeutic candidates for clinical use. Nevertheless, this correlation warrants further research.

Role of vitamin D3 in treatment of lumbar disc herniation--pain and sensory aspects: study protocol for a randomized controlled trial

BACKGROUND

Vitamin D receptors have been identified in the spinal cord, nerve roots, dorsal root ganglia and glial cells, and its genetic polymorphism association with the development of lumbar disc degeneration and herniation has been documented. Metabolic effects of active vitamin D metabolites in the nucleus pulposus and annulus fibrosus cells have been studied. Lumbar disc herniation is a process that involves immune and inflammatory cells and processes that are targets for immune regulatory actions of vitamin D as a neurosteroid hormone. In addition to vitamin D's immune modulatory properties, its receptors have been identified in skeletal muscles. It also affects sensory neurons to modulate pain. In this study, we aim to study the role of vitamin D3 in discogenic pain and related sensory deficits. Additionally, we will address how post-treatment 25-hydroxy vitamin D3 level influences pain and sensory deficits severity. The cut-off value for serum 25-hydroxy vitamin D3 that would be efficacious in improving pain and sensory deficits in lumbar disc herniation will also be studied.

METHODS/DESIGN

We will conduct a randomized, placebo-controlled, double-blind clinical trial. Our study population will include 380 cases with one-level and unilateral lumbar disc herniation with duration of discogenic pain less than 8 weeks. Individuals who do not have any contraindications, will be divided into three groups based on serum 25-hydroxy vitamin D3 level, and each group will be randomized to receive either a single-dose 300,000-IU intramuscular injection of vitamin D3 or placebo. All patients will be under conservative treatment. Pre-treatment and post-treatment assessments will be performed with the McGill Pain Questionnaire and a visual analogue scale. For the 15-day duration of this study, questionnaires will be filled out during telephone interviews every 3 days (a total of five times). The initial and final interviews will be scheduled at our clinic. After 15 days, serum 25-hydroxy vitamin D3 levels will be measured for those who have received vitamin D3 (190 individuals).

TRIAL REGISTRATION

Iranian Registry for Clinical Trials ID: IRCT2014050317534N1 (trial registration: 5 June 2014).

The shunt from the cyclooxygenase to lipoxygenase pathway in human osteoarthritic subchondral osteoblasts is linked with a variable expression of the 5-lipoxygenase-activating protein

Osteoarthritis (OA) is characterized by articular cartilage degradation and hypertrophic bone changes with osteophyte formation and abnormal bone remodeling. Two groups of OA patients were identified via the production of variable and opposite levels of prostaglandin E₂ (PGE₂) or leukotriene B₄ (LTB₄) by subchondral osteoblasts, PGE₂ levels discriminating between low and high subgroups. We studied whether the expression of 5-lipoxygenase (5-LO) or 5-LO-activating protein (FLAP) is responsible for the shunt from prostaglandins to leukotrienes. FLAP mRNA levels varied in low and high OA groups compared with normal, whereas mRNA levels of 5-LO were similar in all osteoblasts. Selective inhibition of cyclooxygenase-2 (COX-2) with NS-398-stimulated FLAP expression in the high OA osteoblasts subgroup, whereas it was without effect in the low OA osteoblasts subgroup. The addition of PGE₂ to the low OA osteoblasts subgroup decreased FLAP expression but failed to affect it in the high OA osteoblasts subgroup. LTB₄ levels in OA osteoblasts were stimulated about twofold by 1,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃) plus transforming growth factor-β (TGF-β), a situation corresponding to their effect on FLAP mRNA levels. Treatments with 1,25(OH)₂D₃ and TGF-β also modulated PGE₂ production. TGF-β stimulated PGE₂ production in both OA osteoblast groups, whereas 1,25(OH)₂D₃ alone had a limited effect but decreased the effect of TGF-β in the low OA osteoblasts subgroup. This modulation of PGE₂ production was mirrored by the synthesis of COX-2. IL-18 levels were only slightly increased in a subgroup of OA osteoblasts compared with normal; however, no relationship was observed overall between IL-18 and PGE₂ levels in normal and OA osteoblasts. These results suggest that the shunt from the production of PGE₂ to LTB₄ is through regulation of the expression of FLAP, not 5-LO, in OA osteoblasts. The expression of FLAP in OA osteoblasts is also modulated differently by 1,25(OH)₂D₃ and TGF-β depending on their endogenous low and high PGE₂ levels.

Implant surface characteristics modulate differentiation behavior of cells in the osteoblastic lineage

This paper reviews the role of surface roughness in the osteogenic response to implant materials. Cells in the osteoblast lineage respond to roughness in cell-maturation-specific ways, exhibiting surface-dependent morphologies and growth characteristics. MG63 cells, a human osteoblast-like osteosarcoma cell line, respond to increasing surface roughness with decreased proliferation and increased osteoblastic differentiation. Alkaline phosphatase activity and osteocalcin production are increased. Local factor production is also affected; production of both TGF-beta 1 and PGE2 is increased. On rougher surfaces, MG63 cells exhibit enhanced responsiveness to 1,25-(OH)2D3. Prostaglandins mediate the effects of surface roughness, since indomethacin prevents the increased expression of differentiation markers in these cells.