PTH1-34 inhibited TNF-α expression and antagonized TNF-α-induced MMP13 expression in MIO mice.

This study aims to investigate the effects and mechanisms of parathyroid hormone [1-34] (PTH1-34) on TNF-α-stimulated mice chondrocytes, as well as cartilage from a meniscus injury induced osteoarthritis (MIO) mice model. The C57BL/6J mice received medial meniscectomy, and then administrated with PTH1-34. The results showed that PTH1-34 administration decreased secondary allodynia and the pain-related transcripts. The IHC, ELISA, Micro-CT imaging and histopathology analysis revealed the significantly improved subchondral plate thickness and bone porosity, the reduced pro-inflammatory cytokines in serum and joint fluid. In vitro, mice chondrocyte was treated with TNF-α or co-cultured with synovial cells. The results showed that TNF-α markedly upregulated the MMP13 expression, and the ERK1/2, NF-κB or PI3K signaling pathway inhibitors could reverse the induction effect of TNF-α on expression of MMP13 in chondrocytes. PTH1-34 alone has no effect on the expression of MMP13 and NF-κB signaling pathways, but the PTH1-34 could reverse the induction effect of TNF-α on MMP13 expression and NF-κB signaling pathway activation in chondrocytes. In addition, PTH1-34 administration inhibited the expression of TNF-α and MMP13, and chondrocyte viability, while the PKA repressor reversed the effect of PTH1-34 in chondrocytes co-cultured with synovial cells. In conclusion, PTH1-34 has an obvious analgesic and anti-inflammatory effect, inhibits the matrix synthesis and alleviates the progression of osteoarthritis. In vitro, PTH1-34 inhibited TNF-α expression and antagonized TNF-α-induced MMP13 expression via the PKA pathway and the NF-κB signaling pathways, respectively.

Análisis genético de enzimas de la vía esteroidal asociadas a efectos adversos musculoesqueléticos de los inhibidores de la aromatasa / Genetic analysis of steroid pathway enzymes associated with adverse musculoskeletal effects of aromatase inhibitors

Objetivos: Identificar putativas variantes funcionales en los genes CYP11A1 y CYP17A1 asociadas a efectos musculoesqueléticos (pérdida acelerada de la masa ósea y artralgias) derivados del tratamiento con inhibidores de la aromatasa (IA). Material y métodos: La cohorte B-ABLE es un estudio prospectivo de mujeres postmenopáusicas con cáncer de mama en tratamiento con IA. La densidad mineral ósea en columna lumbar y cuello femoral se midió mediante densitometría, y el dolor articular mediante escala analógica visual. A partir de polimorfismos de cambio de un nucleótido (SNPs) en los genes CYP11A1 (rs4077581, rs11632698 y rs900798) y CYP17A1 (rs4919686, rs4919683, rs4919687, rs3781287, rs10786712, rs6163, rs743572), asociados previamente con eventos musculoesqueléticos, se construyeron los haplotipos para cada paciente de la cohorte, y se seleccionaron aquellos que mostraron mayor diferencia fenotípica (p<0,05). Dentro de cada haplotipo, se eligieron aquellas pacientes con fenotipos extremos para la secuenciación de los respectivos genes y la identificación de variantes genéticas funcionales. Finalmente, se realizó un análisis de regresión lineal múltiple contemplando los modelos de herencia genética dominante, recesivo y aditivo. Resultados: No se encontró ninguna mutación en las regiones codificantes. En la región del promotor basal del gen CYP11A1 se encontró una variante genética (D15S520) asociada a la pérdida de masa ósea del cuello de fémur a los 24 meses de tratamiento con IA. Conclusiones: Variantes en regiones reguladoras del gen CYP11A1 podrían modular la expresión de este gen, explicando así parte de la variabilidad fenotípica encontrada en la pérdida de hueso de las pacientes en tratamiento con IA (AU)

Objetives: Identify putative functional variants in the CYP11A1 and CYP17A1 genes associated with musculoskeletal effects (accelerated bone mass loss and arthralgia) derived from treatment with aromatase inhibitors (AI). Material and methods: The B-ABLE cohort is a prospective study of postmenopausal women with breast cancer undergoing AI treatment. Bone mineral density in the lumbar spine and femoral neck was measured by densitometry and joint pain using visual analogue scale. From single-nucleotide polymorphisms (SNPs) in genes CYP11A1 (rs4077581, rs11632698 and rs900798) and CYP17A1 (rs4919686, rs4919683, rs4919687, rs3781287, rs10786712, rs6163, rs743572), previously associated with musculoskeletal events, haplotypes were constructed for each pacient from the cohort, and those haplotypes that showed greatest phenotypic differences were chosen (p<0.05). Within each haplotype, patients with extreme phenotypes were chosen for the sequencing of respective genes and identifying functional genetic variants. Finally, a multiple linear regression analysis was carried out considering the models of dominant, recessive and additive genetic inheritance. Results: No mutation was found in coding regions. A genetic variant (D15S520), in the basal promoter region of gene CYP11A1, was found associated with femoral neck bone loss at 24 month of AI treatment. Conclusions: Variants in regulatory regions of the CYP11A1 gene could modulate the expression of this gene, thus explaining part of the phenotypic variability found in bone loss of patients undergoing AI treatment (AU)

Naringenin regulates production of matrix metalloproteinases in the knee-joint and primary cultured articular chondrocytes and alleviates pain in rat osteoarthritis model.

Inflammation of cartilage is a primary symptom for knee-joint osteoarthritis. Matrix metalloproteinases (MMPs) are known to play an important role in the articular cartilage destruction related to osteoarthritis. Naringenin is a plant-derived flavonoid known for its anti-inflammatory properties. We studied the effect of naringenin on the transcriptional expression, secretion and enzymatic activity of MMP-3 in vivo in the murine monosodium iodoacetate (MIA) osteoarthritis model. The assessment of pain behavior was also performed in the MIA rats. The destruction of knee-joint tissues was analyzed microscopically. Moreover, the effect of naringenin was also studied in vitro in IL-1ß activated articular chondrocytes. The transcriptional expression of MMP-3, MMP-1, MMP-13, thrombospondin motifs (ADAMTS-4) and ADAMTS-5 was also studied in primary cultured chondrocytes of rats. Naringenin caused significant reduction in pain behavior and showed marked improvement in the tissue morphology of MIA rats. Moreover, a significant inhibition of MMP-3 expression in MIA rats was observed upon treatment with naringenin. In the in vitro tests, naringenin caused a significant reduction in the transcriptional expression, secretion and enzymatic activity of the studied degradative enzymes. The NF-κB pathway was also found to be inhibited upon treatment with naringenin in vitro. Overall, the study suggests that naringenin alleviated pain and regulated the production of matrix-metalloproteinases via regulation of NF-κB pathway. Thus, naringenin could be a potent therapeutic option for the treatment of osteoarthritis.

Naringenin regulates production of matrix metalloproteinases in the knee-joint and primary cultured articular chondrocytes and alleviates pain in rat osteoarthritis model

Inflammation of cartilage is a primary symptom for knee-joint osteoarthritis. Matrix metalloproteinases (MMPs) are known to play an important role in the articular cartilage destruction related to osteoarthritis. Naringenin is a plant-derived flavonoid known for its anti-inflammatory properties. We studied the effect of naringenin on the transcriptional expression, secretion and enzymatic activity of MMP-3 in vivo in the murine monosodium iodoacetate (MIA) osteoarthritis model. The assessment of pain behavior was also performed in the MIA rats. The destruction of knee-joint tissues was analyzed microscopically. Moreover, the effect of naringenin was also studied in vitro in IL-1β activated articular chondrocytes. The transcriptional expression of MMP-3, MMP-1, MMP-13, thrombospondin motifs (ADAMTS-4) and ADAMTS-5 was also studied in primary cultured chondrocytes of rats. Naringenin caused significant reduction in pain behavior and showed marked improvement in the tissue morphology of MIA rats. Moreover, a significant inhibition of MMP-3 expression in MIA rats was observed upon treatment with naringenin. In the in vitro tests, naringenin caused a significant reduction in the transcriptional expression, secretion and enzymatic activity of the studied degradative enzymes. The NF-κB pathway was also found to be inhibited upon treatment with naringenin in vitro. Overall, the study suggests that naringenin alleviated pain and regulated the production of matrix-metalloproteinases via regulation of NF-κB pathway. Thus, naringenin could be a potent therapeutic option for the treatment of osteoarthritis.

Participation of microglial p38 MAPK in formalin-induced temporomandibular joint nociception in rats.

AIMS: To investigate nociceptive behavior and the immunoreactivity of microglia and phosphorylated-p38 (p-p38) mitogen-activated protein kinase (MAPK) following intracisternal administration of SB203580, a p38 MAPK inhibitor, or minocycline, a microglia inhibitor, in rats with temporomandibular joint (TMJ) inflammation. METHODS: The number of nociceptive behavioral responses was recorded for nine successive 5-minute intervals following formalin injections into the left TMJ. SB203580 or minocycline was administered intracisternally 2 hours prior to the formalin injection. Statistical analysis used one-way analysis of variance followed by least significant difference post-hoc analysis. RESULTS: The intra-articular injection of formalin increased the expression of p-p38 MAPK in the ipsilateral medullary dorsal horn. Most of the p-p38 MAPK co-localized with OX42, a microglial marker, but not with GFAP, an astrocyte marker. Intracisternal injections of SB203580 (0.5, 1, or 5 Μg) attenuated the number of nociceptive behavioral responses and the expression of p-p38 MAPK in the medullary dorsal horn. Intracisternal injections of minocycline (25 or 50 Μg) also attenuated the responses and the expression of OX42 and p-p38 MAPK in the medullary dorsal horn. CONCLUSION: These findings suggest that p38 MAPK in microglia plays an important role in the central processing of inflammatory TMJ nociception in rats. The data further indicate that a targeted blockade of the microglial p38 MAPK pathway is a potentially important new treatment strategy for inflammatory TMJ nociception.

The expanding use of third-generation aromatase inhibitors: what the general internist needs to know.

BACKGROUND: Breast cancer patients represent the largest group of adult cancer survivors in the US. Most breast cancers in women 50 years of age and older are hormone receptor positive. Third generation aromatase inhibitors (AIs) are the newest class of drugs used in treating hormone responsive breast cancer. It is often during start of adjuvant hormone therapy that the breast cancer patient establishes (or reestablishes) close follow-up with their general internist. OBJECTIVE: Given the large numbers of breast cancer patients in the US and the increasing use of third generation AI's, general internists will need to have a clear understanding of these drugs including their benefits and potential harms. Currently there are three third generation aromatase inhibitors FDA approved for use in the US. All have been shown to be superior to tamoxifen in disease free survival (DFS) in the treatment of both metastatic and early breast cancers. RESULTS: While the data on side effects is limited, AI (compared to tamoxifen) may result in higher rates of osteoporosis and fractures, more arthralgias, and increased vaginal dryness and dysparuenia. Limited information on their effects on the cardiovascular system and neuro-cognitive function are also available. Patient's receiving adjuvant hormone therapy are generally considered disease free or disease stable and require less intensive monitoring by their breast cancer specialist. CONCLUSIONS: In situations where patients experience significant negative side effects from AI therapy, discussions to discontinue treatment (and switch to an alternative endocrine therapy) should involve the cancer specialist and take into consideration the patient's risk for breast cancer recurrence and the impact of therapy on their quality of life. In some cases, patients may choose to never initiate AI treatment. In other cases, patients may choose to prematurely discontinue therapy even if therapy is well tolerated. In both settings increased knowledge by the general internists will likely facilitate discussions of risks versus benefits of therapy and possibly improve compliance to adjuvant hormone therapy.

The discriminating value of serum lactate dehydrogenase levels in children with malignant neoplasms presenting as joint pain.

OBJECTIVES: To determine if serum lactate dehydrogenase levels distinguish patients with malignant neoplasm presenting with musculoskeletal complaints from patients with juvenile rheumatoid arthritis who reported similar symptoms. DESIGN: Retrospective case-comparison study. SETTING: Tertiary care, outpatient clinics. PATIENTS: Twelve patients with malignant neoplasms who presented with arthritis or arthralgias and normal complete blood cell counts and blood smears in whom rheumatologic diagnosis was initially made were compared with 24 children with a final diagnosis of juvenile rheumatoid arthritis. The patients with malignant neoplasms all had normal blood counts and elevated sedimentation rates at symptom onset. INTERVENTIONS: None. RESULTS: Serum lactate dehydrogenase levels were significantly higher in the cancer patients at 2.2 times the normal values vs 0.8 times high normal for patients with juvenile rheumatoid arthritis (P =.004, Mann-Whitney U test) No significant differences were observed in white blood cell counts, hemoglobin levels, platelet counts, erythrocyte sedimentation rate, or uric acid or aspartate aminotransferase levels at initial evaluation. CONCLUSIONS: Serum lactate dehydrogenase values may distinguish patients with malignant neoplasms from those with rheumatic disease early in the course of illness when symptoms and other laboratory values are not helpful.