Pentosidine concentration is associated with degenerative lumbar scoliosis in older women: preliminary results

Association between Osteoporosis and Skeletal Muscle Mass in Men

STUDY DESIGN

Cross-sectional study.

PURPOSE

This cross-sectional study aimed to investigate the risk factors for osteoporosis in men by assessing bone mineral density (BMD), skeletal muscle mass, body fat mass, grip strength, and advanced glycation end products (AGEs).

OVERVIEW OF LITERATURE

Fewer studies have reported the correlation between BMD and skeletal muscle mass in women. Moreover, a few studies have examined the relationship between osteoporosis and skeletal muscle mass.

METHODS

This study included 99 men (mean age, 74.9 years; range, 28-93 years) who visited Qiball Clinic for BMD and body composition examinations. The osteoporosis group consisted of 24 patients (mean age, 72.5 years; range, 44-92 years), and the control group consisted of 75 individuals (mean age, 74.9 years; range, 28-93 years). Whole-body skeletal muscle mass was measured using a bioelectrical impedance analyzer. BMD was measured by dual X-ray absorptiometry. Skin autofluorescence (SAF), a marker of dermal AGE accumulation, was measured using a spectroscope. Osteoporosis was defined as a bone density T score of -2.5 or less. Physical findings, skeletal muscle mass, BMD, grip strength, and SAF were compared between the osteoporosis and control groups.

RESULTS

The osteoporosis group had significantly lower trunk muscle mass (23.1 kg vs. 24.9 kg), lower leg muscle mass (14.4 kg vs. 13.0 kg), and skeletal mass index (7.1 kg/m2 vs. 6.7 kg/m2) than the control group (all p<0.05). Lower limb muscle mass was identified as a risk factor for osteoporosis in men (odds ratio, 0.64; p=0.03).

CONCLUSIONS

Conservative treatment of osteoporosis in men will require an effective approach that facilitates the maintenance or strengthening of skeletal muscle mass, including exercise therapy with a focus on lower extremities and nutritional supplementation.

Biological principles of adult degenerative scoliosis

The global aging population has led to an increase in geriatric diseases, including adult degenerative scoliosis (ADS). ADS is a spinal deformity affecting adults, particularly females. It is characterized by asymmetric intervertebral disc and facet joint degeneration, leading to spinal imbalance that can result in severe pain and neurological deficits, thus significantly reducing the quality of life. Despite improved management, molecular mechanisms driving ADS remain unclear. Current literature primarily comprises epidemiological and clinical studies. Here, we investigate the molecular mechanisms underlying ADS, with a focus on angiogenesis, inflammation, extracellular matrix remodeling, osteoporosis, sarcopenia, and biomechanical stress. We discuss current limitations and challenges in the field and highlight potential translational applications that may arise with a better understanding of these mechanisms.

Osteosarcopenia in the Spine Beyond Bone Mineral Density: Association Between Paraspinal Muscle Impairment and Advanced Glycation Endproducts

STUDY DESIGN

Prospective cross-sectional study.

OBJECTIVE

To determine if an accumulation of advanced glycation endproducts (AGEs) is associated with impaired paraspinal muscle composition.

BACKGROUND

Impaired bone integrity and muscle function are described as osteosarcopenia. Osteosarcopenia is associated with falls, fragility fractures, and reduced quality of life. Bone integrity is influenced by bone quantity (bone mineral density) and quality (microarchitecture and collagen). The accumulation of AGEs stiffens collagen fibers and increases bone fragility. The relationship between paraspinal muscle composition and bone collagen properties has not been evaluated.

METHODS

Intraoperative bone biopsies from the posterior superior iliac spine were obtained and evaluated with multiphoton microscopy for fluorescent AGE cross-link density (fAGEs). Preoperative magnetic resonance imaging measurements at level L4 included the musculus (m.) psoas and combined m. multifidus and m. erector spinae (posterior paraspinal musculature, PPM). Muscle segmentation on axial images (cross-sectional area, CSA) and calculation of a pixel intensity threshold method to differentiate muscle (functional cross-sectional area, fCSA) and intramuscular fat (FAT). Quantitative computed tomography was performed at the lumbar spine. Univariate and multivariable regression models were used to investigate associations between fAGEs and paraspinal musculature.

RESULTS

One hundred seven prospectively enrolled patients (50.5% female, age 60.7 y, BMI 28.9 kg/m 2 ) were analyzed. In all, 41.1% and 15.0% of the patients demonstrated osteopenia and osteoporosis, respectively. Univariate linear regression analysis demonstrated a significant association between cortical fAGEs and CSA in the psoas (ρ=0.220, P =0.039) but not in the PPM. Trabecular fAGEs revealed no significant associations to PPM or psoas musculature. In the multivariable analysis, higher cortical fAGEs were associated with increased FAT (β=1.556; P =0.002) and CSA (β=1.305; P =0.005) in the PPM after adjusting for covariates.

CONCLUSION

This is the first investigation demonstrating that an accumulation of nonenzymatic collagen cross-linking product fAGEs in cortical bone is associated with increased intramuscular fat in the lumbar paraspinal musculature.

Post-translational regulation of muscle growth, muscle aging and sarcopenia

Skeletal muscle makes up 30-40% of the total body mass. It is of great significance in maintaining digestion, inhaling and exhaling, sustaining body posture, exercising, protecting joints and many other aspects. Moreover, muscle is also an important metabolic organ that helps to maintain the balance of sugar and fat. Defective skeletal muscle function not only limits the daily activities of the elderly but also increases the risk of disability, hospitalization and death, placing a huge burden on society and the healthcare system. Sarcopenia is a progressive decline in muscle mass, muscle strength and muscle function with age caused by environmental and genetic factors, such as the abnormal regulation of protein post-translational modifications (PTMs). To date, many studies have shown that numerous PTMs, such as phosphorylation, acetylation, ubiquitination, SUMOylation, glycosylation, glycation, methylation, S-nitrosylation, carbonylation and S-glutathionylation, are involved in the regulation of muscle health and diseases. This article systematically summarizes the post-translational regulation of muscle growth and muscle atrophy and helps to understand the pathophysiology of muscle aging and develop effective strategies for diagnosing, preventing and treating sarcopenia.

Genetic and serum markers in adult degenerative scoliosis: a literature review

STUDY DESIGN

Literature review.

OBJECTIVE

Adult degenerative scoliosis (ADS) is becoming a more prevalent diagnosis with an increasing elderly population. Our objective is to provide a literature review of genetic and serum markers in ADS.

METHODS

A literature review was conducted in the various databases from their inception to July 2020. Studies that reviewed any genetic or serum markers of ADS whether in detection or progression were selected. Studies that reviewed congenital scoliosis or adolescent idiopathic scoliosis (AIS) were excluded.

RESULTS

A total of 1447 titles were identified of which 14 were included in the final review. Two papers reported on serum markers pertaining to serum cartilage metabolites and pentosidine. Twelve studies reported on genetic markers including gene polymorphisms in estrogen receptors, parathyroid hormone receptors, interleukin 6, cyclooxygenase-2 (COX-2), COL2A1, GPRIN1, TRAIL, GRIN receptor, RIMS, LBX1 as well as copy number variations.

CONCLUSIONS

Serum markers of osteoarthritis and sarcopenia have been found to be significantly elevated in ADS patients as well. Numerous polymorphisms have been found in a variety of genes playing key roles in bone formation and regulation. Further research is needed in validating previous studies as well as identifying other biomarkers for patients at risk for developing ADS.

A 2-year longitudinal study of skeletal muscle mass in women over 40 years of age with degenerative lumbar scoliosis

PURPOSE

We investigated changes in skeletal muscle mass and bone mineral density in degenerative lumbar scoliosis (DLS) patients during a 2-year follow-up following diagnosis.

METHOD

This study included 418 Japanese women, identifying 50 patients for the DLS group (mean age 76.4 years) and 368 patients for the control group (mean age 73.4 years). Whole-body skeletal muscle mass was measured using a Bioelectrical Impedance Analyzer. Bone mineral density (BMD) was measured using DXA. Skin autofluorescence (SAF), a marker of advanced glycation end products in the skin, was measured using a spectroscope. Spinal alignment, skeletal muscle mass, BMD, grip strength, and SAF were examined and the amount of change 1 and 2 years from the initial examination for each item was compared between groups.

RESULTS

Height, body fat mass, grip strength, upper limb muscle mass, and trunk muscle mass in the DLS group were significantly lower, and lumbar spine BMD was significantly greater compared to controls at the first visit (p < 0.05). There was no significant difference in spinal alignment in the DLS group after 2 years compared with baseline. Trunk muscle mass also decreased significantly more in the DLS group (-2.7%) than in the control group (-1.1%) over the 2-year follow-up (p < 0.05).

DISCUSSION

In this study, trunk muscle mass in the DLS group decreased about 2.4 times more in 2 years compared with the control group (p < 0.05). It may be possible to clarify the mechanism of kyphoscoliosis progression in the future with large-scale longitudinal studies.

The potential role of dietary advanced glycation endproducts in the development of chronic non-infectious diseases: a narrative review

Increasing clinical and experimental evidence accumulated during the past few decades supports an important role for dietary advanced glycation endproducts (AGE) in the pathogenesis of many chronic non-infectious diseases, such as type 2 diabetes, CVD and others, that are reaching epidemic proportions in the Western world. Although AGE are compounds widely recognised as generated in excess in the body in diabetic patients, the potential importance of exogenous AGE, mostly of dietary origin, has been largely ignored in the general nutrition audience. In the present review we aim to describe dietary AGE, their mechanisms of formation and absorption into the body as well as their main mechanisms of action. We will present in detail current evidence of their potential role in the development of several chronic non-infectious clinical conditions, some general suggestions on how to restrict them in the diet and evidence regarding the potential benefits of lowering their consumption.

Advanced glycation end products are associated with sarcopenia in older women: aging marker dynamics

The aim of this study was to determine whether advanced glycation end products (AGEs) revealed by skin autofluorescence (SAF), serum and urine pentosidine level, and serum homocysteine level can serve as a biomarker for sarcopenia in older women. The participants were 70 elderly women. The AGEs pentosidine, homocysteine, and SAF were measured as aging markers. This study shows that among the biomarkers for aging, serum pentosidine correlates with a loss of appendicular lean mass and can serve as a biomarker for sarcopenia. Moreover, SAF and homocysteine values exhibited a positive correlation with age and correlated with each other.Abbreviations: AGEs: advanced glycation end products; BIA: bioelectrical impedance analyzer; BMD: bone mineral density; DLS: degenerative lumbar scoliosis; DXA: dual-energy X-ray absorptiometry; ELISA: enzyme-linked immunoassay; HHcy: hyperhomocysteinemia; RIA: radioimmunoassay; SAF: skin autofluorescence; SMI: skeletal muscle mass index; T2DM: type 2 diabetes patients.

Sarcopenia is related to spinal sagittal imbalance in patients with spinopelvic mismatch

PURPOSE

To clarify the relationship between sarcopenia and spinopelvic parameters.

METHODS

Among outpatients of spine surgery department, 126 patients (mean age 77.2 years. M/F = 71/55) were included. We diagnosed patients with sarcopenia using the diagnostic algorithm of the Asian Working Group for Sarcopenia. Spinopelvic parameters and the prevalence of spinopelvic mismatch (pelvic incidence minus lumbar lordosis ≥ 10°) were investigated and compared between patients with and without sarcopenia. Furthermore, we compared the spinopelvic parameters between the Sarcopenia and No Sarcopenia groups under each condition of spinopelvic match and mismatch.

RESULTS

The prevalence of sarcopenia in this study was 21.4%. Overall, the spinopelvic parameters except thoracic kyphosis (TK) (Sarcopenia: 34.7°, No Sarcopenia: 24.3°, p < 0.01) were not significantly different between the Sarcopenia and No Sarcopenia groups. Prevalence of patients with spinopelvic mismatch was also not significantly different between the Sarcopenia and No Sarcopenia groups (37.0% vs. 42.4%, p = 0.66). Among patients without spinopelvic mismatch, there was no spinopelvic parameter with a significant difference between the 2 groups. However, among patients with spinopelvic mismatch, sagittal vertebral axis (SVA) (115.7 mm vs. 58.7 mm, p < 0.01) and TK (36.6° vs. 21.3°, p < 0.01) of the Sarcopenia group were significantly larger than those of the No Sarcopenia group. Moreover, sarcopenia was independently related to a significant increase in SVA (β = 50.7, p < 0.01) and TK (β = 14.0, p < 0.01) in patients with spinopelvic mismatch, after adjustment for age.

CONCLUSIONS

Sarcopenia is related to spinal sagittal imbalance because of insufficient compensation by flattening thoracic kyphosis in patients with spinopelvic mismatch. These slides can be retrieved under Electronic Supplementary Material.