Serum calcium concentration as an indicator of intervertebral disk degeneration prognosis

Achilles' Heel-The Significance of Maintaining Microenvironmental Homeostasis in the Nucleus Pulposus for Intervertebral Discs

The dysregulation of intracellular and extracellular environments as well as the aberrant expression of ion channels on the cell membrane are intricately linked to a diverse array of degenerative disorders, including intervertebral disc degeneration. This condition is a significant contributor to low back pain, which poses a substantial burden on both personal quality of life and societal economics. Changes in the number and function of ion channels can disrupt the water and ion balance both inside and outside cells, thereby impacting the physiological functions of tissues and organs. Therefore, maintaining ion homeostasis and stable expression of ion channels within the cellular microenvironment may prove beneficial in the treatment of disc degeneration. Aquaporin (AQP), calcium ion channels, and acid-sensitive ion channels (ASIC) play crucial roles in regulating water, calcium ions, and hydrogen ions levels. These channels have significant effects on physiological and pathological processes such as cellular aging, inflammatory response, stromal decomposition, endoplasmic reticulum stress, and accumulation of cell metabolites. Additionally, Piezo 1, transient receptor potential vanilloid type 4 (TRPV4), tension response enhancer binding protein (TonEBP), potassium ions, zinc ions, and tungsten all play a role in the process of intervertebral disc degeneration. This review endeavors to elucidate alterations in the microenvironment of the nucleus pulposus during intervertebral disc degeneration (IVDD), with a view to offer novel insights and approaches for exploring therapeutic interventions against disc degeneration.

Correlation between serum angiotensin-converting enzyme (ACE) levels and intervertebral disc degeneration

Studies have shown that the renin-angiotensin system (RAS) might play an essential role in intervertebral disc degeneration (IDD). The study aimed to investigate the relationship between serum angiotensin-converting enzyme (ACE) concentration and IDD and its predictive value for severe disc degeneration. 245 patients who came to our hospital for low back pain were recruited, and blood samples were collected for routine examination. Descriptive data and demographic parameters were collected. The cumulative grade 1 was calculated by summing up the Pfirrmann grade of all lumbar discs. ACE concentration grouping was determined via tertile split. Correlation analysis and multivariable linear regression analysis were performed to determine the relationship between ACE and IDD. The receiver's degree of disc degeneration (ROC) curve determined the ACE's predictive value. Results indicated that there was no significant difference in demographic parameters among groups. Correlation analysis and multivariate linear analysis showed that ACE was an independent risk factor for IDD. The cumulative grade 1 increased significantly with the increase in ACE concentration, which was consistent with the correlation analysis. Average Pfirrmann grade < 4 indicates mild to moderate degeneration, and grade ≥ 4 indicates severe degeneration in terms of an individual disc. From L1/2 to L5/S1, the mean plasma ACE concentration was significantly higher in the severe degeneration group than in the mild to moderate degeneration group. According to the ROC curve, the cut-off value of ACE levels was 22.5. patients with ACE > 22.5 had severe degeneration. The sensitivity and specificity were 0.762 and 0.521, respectively.

Preoperative Lymphocyte to Monocyte Ratio as a Predictive Biomarker for Disease Severity and Spinal Fusion Failure in Lumbar Degenerative Diseases Patients Undergoing Lumbar Fusion

Objective

This study was designed to determine whether lymphocyte to monocyte ratio (LMR) correlated with the intervertebral disc degeneration (IDD) severity and the postoperative spinal fusion rate in patients with lumbar disc disease.

Methods

303 patients undergoing posterior lumbar decompression and fusion were retrospectively analyzed. An examination of the blood count was performed before surgery. The cumulative grade was calculated by summing the pfirrmann grades of all lumbar discs. Grouping was based on the 50th percentile of cumulative grade and spinal fusion. The relationship between LMR and IDD severity and spinal fusion was explored using correlation analyses and logistic regression models. The receiver operating characteristic (ROC) curve was performed to measure model discrimination, and Hosmer-Lemeshow (H-L) test was used to measure calibration. Meanwhile, the ROC curve evaluated the discrimination ability of LMR in predicting severe degeneration and fusion failure.

Results

LMR was significantly lower in the severe degeneration group (cumulative grade > 18) than in the mild to moderate degeneration group (cumulative grade ≤ 18). Furthermore, the LMR of the fusion group was significantly higher than that of the non-fusion group. The multivariate binary logistic models revealed that LMR was an independently influencing factor of the severe degeneration and fusion failure (OR: 0.793, 95% CI: 0.638–0.987, p = 0.038; OR: 0.371, 95% CI: 0.258–0.532, p < 0.001). The models showed excellent discrimination and calibration. The area under the curve (AUC) of severe degeneration and fusion failure identified by LMR were 0.635 and 0.643, respectively, and the corresponding cut-off values were 3.16 and 3.90.

Conclusion

LMR is significantly associated with the risk of severe disc degeneration and spinal fusion failure.

Concentration of Selected Macronutrients and Toxic Elements in the Blood in Relation to Pain Severity and Hydrogen Magnetic Resonance Spectroscopy in People with Osteoarthritis of the Spine

Macronutrients and toxic elements may play an important role in the pathogenesis of osteoarthritis of the spine. The objective of this study was to evaluate the relationship between the concentrations of Ca, Mg, Pb, Cd and Hg in blood with the results of hydrogen magnetic resonance spectroscopy and the severity of pain. Patients with osteoarthritis of the spine (n = 90) and control subjects (n = 40) were studied. The concentrations of mineral components in blood were determined by atomic absorption spectrometry (ASA). Spinal pain severity was assessed using the Visual Analog Scale (VAS). Hydrogen magnetic resonance spectroscopy (¹H-MRS) was used to determine the fat/water ratio in the bodies of L1, L5 and the L4/5 intervertebral disc. The median concentration of Mg in the serum of subjects with spinal degenerative disease was significantly lower (p < 0.001) than that in healthy subjects. The median concentration of Cd in the blood of subjects with osteoarthritis of the spine was significantly higher (p < 0.05) than that in the control group. Significantly lower (p < 0.05) median molar ratios of Ca to Cd and Pb as well as Mg to Pb and Cd were observed among patients with osteoarthritis of the spine. Significant differences (p < 0.05) were observed in the value of the fat/water ratio in selected spinal structures, depending on normal or abnormal serum Ca and Mg concentrations. The study showed some abnormal macronutrient concentrations, as well as disturbed ratios of beneficial elements to toxic elements in the blood of people with osteoarthritis of the spine.

Changes in Elements and Relationships among Elements in Intervertebral Disc Degeneration

Intervertebral disc degeneration (IVDD) is a complex and progressive process of disc aging. One of the most important causes of changes in the internal environment, leading to IVDD, can be changes in the concentration of individual metal elements. This study aimed to analyze the concentrations of copper, iron, manganese, lead, zinc, sodium, potassium, phosphorus, and calcium in the degenerated intervertebral discs of the lumbosacral spine, compared to healthy intervertebral discs. The study group (S) consisted of 113 Caucasian patients, qualified by a specialist surgeon for IVDD of the lumbosacral spine. The control group (C) consisted of 81 individuals. The biological material was obtained from Caucasian human cadavers during post-mortem examination. The concentrations of individual elements were assessed using inductively coupled plasma−optical emission spectroscopy (ICP-OES). Statistically significant differences in the concentrations of microelements, depending on the degree of pain intensity, were noted for only potassium (p < 0.05). Statistically significant differences in the concentrations of the assessed microelements, depending on the degree of radiological advancement of the lesions, were noted for copper and iron (p < 0.05). In the degenerated intervertebral discs, the strongest relationships were noted between the concentrations of zinc and lead (r = 0.67; p < 0.05), zinc and phosphorus (r = 0.74; p < 0.05), and zinc and calcium (r = 0.77; p < 0.05). It has been indicated that, above all, the concentrations of copper and iron depend on the advancement of radiological changes, according to the Pfirrmann scale; however, no influence on the pain intensity, depending on the concentration of the assessed elements, was found.

Atomic absorption spectrometry analysis of trace elements in degenerated intervertebral disc tissue

Background

Few studies have investigated trace elements (TE) in human intervertebral disc (IVD) tissue.

Trace element presence can have diverse meanings: essential TE show the metabolic modalities of the tissue, while environmentally-related TE indicate pollution and tissue-specific absorption and accumulation.

IVD is a highly specific compartment with impaired communication with adjacent bone. Analysis of TE in IVD provides new insights regarding tissue metabolism and IVD communication with other tissues.

Material/Methods

Thirty intervertebral discs were acquired from 22 patients during surgical treatment for degenerative disease. Atomic absorption spectrometry was used to evaluate the concentrations of Al, Cd, Pb, Cu, Ni, Mo, Mg, and Zn.

Results

Al, Pb, Cu, Mg, and Zn were detected in all samples. Pb was significantly positively correlated with age, and Ni concentration was weakly correlated with population count in the patient’s place of residence. Only Cu was observed in higher concentrations in IVD compared to in other tissues. Significant positive correlations were observed between the following pairs: Mg/Zn, Mg/Al, Mg/Pb, Zn/Al, Zn/Pb, and Al/Pb. Negative correlations were observed between Mg/Cd, Zn/Cd, Mg/Mo, and Mo/Pb.

Conclusions

This study is one of few to profile the elements in intervertebral discs in patients with degenerative changes. We report significant differences between trace element concentrations in intervertebral discs compared to in other tissues. Knowledge of the TE accumulation pattern is vital for better understanding intervertebral disc nutrition and metabolism.

Comparison of trace element concentration in bone and intervertebral disc tissue by atomic absorption spectrometry techniques

BACKGROUND

Trace element (TE) analysis in human tissue has the dual purpose of assessing environmental pollution and metabolism. In literature, bone TE analysis is common, but studies in intervertebral disc (IVD) tissue are lacking. The aim of the study was evaluation of the difference of TE concentration in intervertebral disc and bone in patients with degenerative changes. The comparison of the tissues differing in metabolism, blood perfusion, or separateness from adjoining tissues but playing similar biomechanical role and presenting some common morphological traits may shed new light on metabolism nuances, degenerative process, as well as accumulation potential of IVD in respect to bone.

METHODS

In the study, we analyzed two types of samples: intervertebral disc (n =30, from 22 patients operated due to degenerative disc disease) and femoral bone (n =26, separately femoral head and neck, from 26 patients, acquired in total hip arthroplasty procedure in course of idiopathic osteoarthritis of the hip joint). In the samples we analyzed, with atomic absorption spectrometry, the concentrations of Pb, Ni, Mo, Cu, Mg, and Zn.

RESULTS

The element concentrations identified in bone are comparable to those presented in the literature. In the case of Pb, Ni, Mo, Mg, and Zn, the concentration in the bone was 2 to 25.8 times higher than that observed in the disc. Only the Cu concentration was higher in disc tissue than in bone. In disc tissue, fewer samples had TE concentrations below the detection threshold. We found significant differences in TE profiles in the compared tissues.

CONCLUSIONS

The results show that the disc could serve as a more stable compartment for evaluating TE concentration, especially for TEs that are environmentally related.