Osteoporosis and fractures in liver disease: Relevance, pathogenesis and therapeutic implications

Associations of metabolic dysfunction-associated fatty liver disease and hepatic fibrosis with bone mineral density and risk of osteopenia/osteoporosis in T2DM patients

Background

Existing evidence on the associations of liver steatosis and fibrosis with bone mineral density (BMD) and risk of osteopenia/osteoporosis was limited with conflicting results. We aimed to evaluate the associations of metabolic dysfunction-associated fatty liver disease (MAFLD) and hepatic fibrosis with BMD and risk of osteopenia/osteoporosis in type 2 diabetes mellitus (T2DM) patients.

Methods

Baseline information of an ongoing cohort of 249 T2DM patients in Xiamen, China was analyzed. MAFLD was defined as the presence of hepatic steatosis [diagnosed by either hepatic ultrasonography scanning or fatty liver index (FLI) score >60] for T2DM patients. BMD was measured using dual-energy x-ray absorptiometry at total lumbar (L2-4), femur neck (FN), and total hip (TH) and was categorized as normal (T ≥ -1.0), osteopenia (-2.5 < T < -1.0), or osteoporosis (T ≤ -2.5) according to its minimum T-score.

Results

Among the 249 T2DM patients, prevalence rates of MAFLD, osteopenia, and osteoporosis were 57.8%, 50.6%, and 17.7%, respectively. Patients with MAFLD had significantly higher BMD T-scores of L2-4, FN, and TH and the minimum as well as lower prevalence of osteoporosis than patients without MAFLD. Hepatic steatosis indices, including FLI score, fatty liver (FLI ≥ 60 or hepatic ultrasonography scanning), and MAFLD, were significantly and positively associated with all T-scores, while hepatic fibrosis index and FIB-4 score, but not NAFLD fibrosis score (NFS), were negatively associated with all T-scores. MAFLD was significantly associated with the decreased risk of osteopenia/osteoporosis and osteoporosis with unadjusted odds ratios (ORs) (95% CI) of 0.565 (0.324-0.987) and 0.434 (0.224-0.843) (both p-values < 0.05), respectively. As for liver fibrosis, FIB-4 score, but not NFS, was significantly associated with elevated risk of osteoporosis with an unadjusted OR (95% CI) per SD increase of FIB-4 score of 1.446 (1.080-1.936, p-value = 0.013). Adjusting for potential confounding variables, especially body mass index, in the multivariable regression analyses, all associations of hepatic steatosis and fibrosis indices with BMD and risk of osteopenia/osteoporosis were not statistically significant.

Conclusion

MAFLD and hepatic fibrosis were not significantly associated with BMD and risk of osteopenia/osteoporosis independent of obesity. Nevertheless, screening and management of MAFLD and osteopenia/osteoporosis were still important for the prevention of fracture in T2DM patients.

SIRT2 regulates extracellular vesicle-mediated liver-bone communication

The interplay between liver and bone metabolism remains largely uncharacterized. Here, we uncover a mechanism of liver-bone crosstalk regulated by hepatocyte SIRT2. We demonstrate that hepatocyte SIRT2 expression is increased in aged mice and elderly humans. Liver-specific SIRT2 deficiency inhibits osteoclastogenesis and alleviates bone loss in mouse models of osteoporosis. We identify leucine-rich α-2-glycoprotein 1 (LRG1) as a functional cargo in hepatocyte-derived small extracellular vesicles (sEVs). In SIRT2-deficient hepatocytes, LRG1 levels in sEVs are upregulated, leading to increased transfer of LRG1 to bone-marrow-derived monocytes (BMDMs), and in turn, to inhibition of osteoclast differentiation via reduced nuclear translocation of NF-κB p65. Treatment with sEVs carrying high levels of LRG1 inhibits osteoclast differentiation in human BMDMs and in mice with osteoporosis, resulting in attenuated bone loss in mice. Furthermore, the plasma level of sEVs carrying LRG1 is positively correlated with bone mineral density in humans. Thus, drugs targeting hepatocyte-osteoclast communication may constitute a promising therapeutic strategy for primary osteoporosis.

Bone loss in chronic liver diseases: Could healthy liver be a requirement for good bone health?

Given that the liver is involved in many metabolic mechanisms, it is not surprising that chronic liver disease (CLD) could have numerous complications. Secondary osteoporosis and increased bone fragility are frequently overlooked complications in CLD patients. Previous studies implied that up to one-third of these individuals meet diagnostic criteria for osteopenia or osteoporosis. Recent publications indicated that CLD-induced bone fragility depends on the etiology, duration, and stage of liver disease. Therefore, the increased fracture risk in CLD patients puts a severe socioeconomic burden on the health system and urgently requires more effective prevention, diagnosis, and treatment measures. The pathogenesis of CLD-induced bone loss is multifactorial and still insufficiently understood, especially considering the relative impact of increased bone resorption and reduced bone formation in these individuals. It is essential to note that inconsistent findings regarding bone mineral density measurement were previously reported in these individuals. Bone mineral density is widely used as the “golden standard” in the clinical assessment of bone fragility although it is not adequate to predict individual fracture risk. Therefore, microscale bone alterations (bone microstructure, mechanical properties, and cellular indices) were analyzed in CLD individuals. These studies further support the thesis that bone strength could be compromised in CLD individuals, implying that an individualized approach to fracture risk assessment and subsequent therapy is necessary for CLD patients. However, more well-designed studies are required to solve the bone fragility puzzle in CLD patients.

Using network pharmacology and molecular docking verification to explore the mechanism of ursolic acid in the treatment of osteoporosis

Whether ursolic acid is an effective drug in treatment of osteoporosis (OP) and how it exhibit activity effect on OP is unclear. To investigated the potential molecular mechanism of ursolic acid in the treatment of OP and figured out its possible mechanism is necessary. The target genes of ursolic acid were screened by using the database of traditional chinese medicine systems pharmacology, PubMed database and UniProt database. OP-related target genes were searched by GeneCards database, and utilized online mapping tool to obtain common target genes of component-disease. String database was used to construct a protein-protein interaction (PPI) network of component-disease common target genes and perform topological analysis to screen core target genes. DAVID database was performed gene ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis for component-disease shared target genes. Using the core target protein as the receptor and ursolic acid as the ligand, the molecular docking was performed using AutoDockVina 1.1.2 software. A total of 52 ursolic acid-related target genes and 4657 OP-related target genes were excavated, with a total of collective 43 target genes. The above-mentioned PPI network with shared target genes contains 43 nodes and 510 edges, with an average node degree value of 23.32. A total of 24 core target genes were obtained, mainly including tumor protein p53 (TP53), vascular endothelial growth factor A (VEGFA), interleukin-6 (IL6), tumor necrosis factor (TNF), caspase3 (CASP3), matrix metallo protein (MMP9), transcription factor AP-1 (JUN), activator of transcription 3 (STAT3), mitogen-activated protein kinase 8 (MAPK8), and prostaglandin endoperoxidase 2 (PTGS2), respectively. According to KEGG enrichment analysis, there are 126 treatment of OP signaling pathway were enriched. GO enrichment analysis revealed that 313 biological processes were identified. The molecular docking result showed that the binding energies were all lower than -5 kcal/mol, indicating strong binding activity to the protein by the 6 core target gene. The therapeutic effect of ursolic acid on OP may be achieved by regulating TP53, JUN, IL6, VEGFA, CASP3, and MAPK8 genes, respectively. It exhibits possible biological function in the treatment of OP mainly involve positive regulation of apoptotic process, response to drug, incytoplasm, cytosol, protein binding, identical protein binding. Its mechanism may related to multiple therapeutic targets and signaling pathways such as cancer pathway, hepatitis B, and TNF signaling pathway.

Increased risk of non-alcoholic fatty liver disease fibrosis is closely associated with osteoporosis in women but not in men with type 2 diabetes

Background

This study aimed to investigate the association of non-alcoholic fatty liver disease (NAFLD) and liver fibrosis with osteoporosis in postmenopausal women and men over 50 years of age with type 2 diabetes (T2DM).

Methods

In this study, 1243 patients with T2DM (T2DM with coexistent NAFLD, n = 760; T2DM with no NAFLD, n = 483) were analysed. Non-invasive markers, NAFLD fibrosis score (NFS) and fibrosis index based on four factors (FIB-4), were applied to evaluate NAFLD fibrosis risk.

Results

There was no significant difference in bone mineral density (BMD) between the NAFLD group and the non-NAFLD group or between males and females after adjusting for age, BMI and gender. In postmenopausal women, there was an increased risk of osteoporosis (odds ratio (OR): 4.41, 95% CI: 1.04-18.70, P = 0.039) in the FIB-4 high risk group compared to the low risk group. Similarly, in women with high risk NFS, there was an increased risk of osteoporosis (OR: 5.98, 95% CI: 1.40-25.60, P = 0.043) compared to the low risk group. Among men over 50 years old, there was no significant difference in bone mineral density between the NAFLD group and the non-NAFLD group and no significant difference between bone mineral density and incidence of osteopenia or osteoporosis among those with different NAFLD fibrosis risk.

Conclusion

There was a significant association of high risk for NAFLD liver fibrosis with osteoporosis in postmenopausal diabetic women but not men. In clinical practice, gender-specific evaluation of osteoporosis is needed in patients with T2DM and coexistent NAFLD.

Tourniquet use following blast-associated complex lower limb injury and traumatic amputation promotes end organ dysfunction and amplified heterotopic ossification formation

BACKGROUND

Traumatic heterotopic ossification (tHO) is characterized by ectopic bone formation in extra-skeletal sites leading to impaired wound healing, entrapment of neurovascular structures, pain, and reduced range of motion. HO has become a signature pathology affecting wounded military personnel who have sustained blast-associated traumatic amputations during the recent conflicts in Iraq and Afghanistan and can compound recovery by causing difficulty with prosthesis limb wearing. Tourniquet use to control catastrophic limb hemorrhage prior to surgery has become almost ubiquitous during this time, with the recognition the prolonged use may risk an ischemia reperfusion injury and associated complications. While many factors influence the formation of tHO, the extended use of tourniquets to limit catastrophic hemorrhage during prolonged field care has not been explored.

METHODS

Utilizing an established pre-clinical model of blast-associated complex lower limb injury and traumatic amputation, we evaluated the effects of tourniquet use on tHO formation. Adult male rats were subjected to blast overpressure exposure, femur fracture, and soft tissue crush injury. Pneumatic tourniquet (250-300 mmHg) applied proximal to the injured limb for 150-min was compared to a control group without tourniquet, before a trans-femoral amputation was performed. Outcome measures were volume to tHO formation at 12 weeks and changes in proteomic and genomic markers of early tHO formation between groups.

RESULTS

At 12 weeks, volumetric analysis with microCT imaging revealed a 70% increase in total bone formation (p = 0.007) near the site of injury compared to rats with no tourniquet time in the setting of blast-injuries. Rats subjected to tourniquet usage had increased expression of danger-associated molecular patterns (DAMPs) and end organ damage as early as 6 h and as late as 7 days post injury. The expressions of pro-inflammatory cytokines and chemokines and osteochondrogenic genes using quantitative RT-PCR similarly revealed increased expression as early as 6 h post injury, and these genes along with hypoxia associated genes remained elevated for 7 days compared to no tourniquet use.

CONCLUSION

These findings suggest that tourniquet induced ischemia leads to significant increases in key transcription factors associated with early endochondral bone formation, systemic inflammatory and hypoxia, resulting in increased HO formation.

Structural and Metabolic Changes in Bone

Simple Summary

Bone is an extremely metabolically active tissue that is regenerated and repaired over its lifetime by bone remodeling. Most bone diseases are caused by abnormal restructure processes that undermine bone structure and mechanical strength and trigger clinical symptoms, such as pain, deformity, fracture, and abnormalities of calcium and phosphate homoeostasis. The article examines the main aspects of bone development, anatomy, structure, and the mechanisms of cell and molecular regulation of bone remodeling.

Abstract

As an essential component of the skeleton, bone tissue provides solid support for the body and protects vital organs. Bone tissue is a reservoir of calcium, phosphate, and other ions that can be released or stored in a controlled manner to provide constant concentration in body fluids. Normally, bone development or osteogenesis occurs through two ossification processes (intra-articular and intra-chondral), but the first produces woven bone, which is quickly replaced by stronger lamellar bone. Contrary to commonly held misconceptions, bone is a relatively dynamic organ that undergoes significant turnover compared to other organs in the body. Bone metabolism is a dynamic process that involves simultaneous bone formation and resorption, controlled by numerous factors. Bone metabolism comprises the key actions. Skeletal mass, structure, and quality are accrued and maintained throughout life, and the anabolic and catabolic actions are mostly balanced due to the tight regulation of the activity of osteoblasts and osteoclasts. This activity is also provided by circulating hormones and cytokines. Bone tissue remodeling processes are regulated by various biologically active substances secreted by bone tissue cells, namely RANK, RANKL, MMP-1, MMP-9, or type 1 collagen. Bone-derived factors (BDF) influence bone function and metabolism, and pathophysiological conditions lead to bone dysfunction. This work aims to analyze and evaluate the current literature on various local and systemic factors or immune system interactions that can affect bone metabolism and its impairments.

Inflammatory response to the ischaemia-reperfusion insult in the liver after major tissue trauma

BACKGROUND

Polytrauma is often accompanied by ischaemia-reperfusion injury to tissues and organs, and the resulting series of immune inflammatory reactions are a major cause of death in patients. The liver is one of the largest organs in the body, a characteristic that makes it the most vulnerable organ after multiple injuries. In addition, the liver is an important digestive organ that secretes a variety of inflammatory mediators involved in local as well as systemic immune inflammatory responses. Therefore, this review considers the main features of post-traumatic liver injury, focusing on the immuno-pathophysiological changes, the interactions between liver organs, and the principles of treatment deduced.

METHODS

We focus on the local as well as systemic immune response involving the liver after multiple injuries, with emphasis on the pathophysiological mechanisms.

RESULTS

An overview of the mechanisms underlying the pathophysiology of local as well as systemic immune responses involving the liver after multiple injuries, the latest research findings, and the current mainstream therapeutic approaches.

CONCLUSION

Cross-reactivity between various organs and cascade amplification effects are among the main causes of systemic immune inflammatory responses after multiple injuries. For the time being, the pathophysiological mechanisms underlying this interaction remain unclear. Future work will continue to focus on identifying potential signalling pathways as well as target genes and intervening at the right time points to prevent more severe immune inflammatory responses and promote better and faster recovery of the patient.

Calcium and Phosphorus Deficiencies in Patients with Liver Cirrhosis

Patients with cirrhosis often develop malnutrition and micronutrient deficiencies, leading to a worse prognosis and increased mortality. Our purpose was to assess the prevalence of micronutrient deficiencies especially calcium and phosphorus in patients with decompensated liver cirrhosis (LC). This was a retrospective study including 143 consecutive patients hospitalized for acute decompensation of cirrhosis, most of them with alcoholic etiology along with viral B or viral C and autoimmune induced cirrhosis. A blood test including minerals was performed on admission. Lower serum calcium levels were found in patients with a more severe forms of LC and also the ones diagnosed with viral and alcoholic LC rather than autoimmune induced LC. Peritoneal ascitic fluid was observed in 51 patients with hypocalcemia and only 24 patients with normal calcium levels had fluid accumulation. Low levels of phosphorus were noted in patients with a more severe form of LC (chi-square: 20.2504; p-value 0.000446). Ascitic fluid was found in patients with low values of phosphorus as well as in those with hypocalcemia (chi-square 5.235; p-value 0.022137). In conclusion, this study confirmed that patients with advanced liver disease had lower values of calcium and phosphorus and a more severe form of LC can be associated with hypocalcemia and hypophosphatemia.

Prognostic Factors of the Inability to Bear Self-Weight at Discharge in Patients with Fragility Femoral Neck Fracture: A 5-Year Retrospective Cohort Study in Thailand

An inability to bear self-weight is one of the unfavorable results in geriatric hip fracture, which needs to be prevented. This study determines pre-operative, intra-operative, and post-operative prognostic factors of the inability to bear self-weight at discharge in patients with fragility femoral neck fracture. This retrospective study was conducted at Chiang Mai University (CMU) hospital with an observational cohort design. Electronic medical records of patients aged ≥ 50 years old with fragility femoral neck fractures between 1 January 2015 and 31 December 2019 were reviewed. Pre-, intra-, and post-operative factors were collected. Ambulation status at discharge time was classified into either ability or inability to bear self-weight. Analysis of prognostic factors was done using multivariable risk ratio regression. In total, 269 patients were recruited in this study. Significantly prognostic factors of inability to bear self-weight at discharge were end-stage renal disease (ESRD), cirrhosis, cerebrovascular disease, pre-fracture ambulatory status, having associated fractures, increasing intra-operative blood loss, and having pressure sore. These prognostic factors could be used to predict patients’ outcomes at discharge. Proper management could then be offered to the patients by the multidisciplinary care team to enhance surgical outcomes.

Chronic liver disease and cirrhosis increase morbidity in geriatric patients treated surgically for hip fractures: analysis of the US Nationwide Inpatient Sample

Background

This study aimed to evaluate the impact of chronic liver disease and cirrhosis on inpatient outcomes of geriatric hip fracture surgery.

Materials and methods

Using population-based retrospective study design, this study extracted data from the US Nationwide Inpatient Sample (NIS) database 2005–2014, identifying patients aged ≥ 65 years undergoing hip fracture repair. Main outcomes were in-hospital mortality, any/specific complications, non-routine discharge, extended length of stay (LOS) and hospital costs. Associations between cirrhosis, non-cirrhotic chronic liver disease and outcomes were determined using regression analysis.

Results

Data of 347,363 hip fracture patients included 344,035 without liver disease, 1257 with non-cirrhotic chronic liver disease and 2,071 with cirrhosis. After adjustments, non-cirrhotic chronic liver disease was significantly associated with non-routine discharge (OR: 1.247, 95% CI: 1.038–1.498), acute kidney injury (OR: 1.266, 95% CI: 1.039–1.541), extended LOS (OR: 1.285, 95% CI: 1.122–1.473) and hospital costs (beta: 9173.42, 95% CI: 6925.9–11,420.95) compared to no liver disease; while cirrhosis was significantly associated with higher risk of in-hospital mortality (OR: 2.325, 95% CI: 1.849–2.922), any complication (OR: 1.295, 95% CI: 1.143–1.467), acute kidney injury (OR: 1.242, 95% CI: 1.177–1.433), non-routine discharge (OR: 1.650, 95% CI: 1.412–1.928), extended LOS (OR: 1.405, 95% CI: 1.263–1.562) and hospital costs (beta: 6680.24, 95% CI: 4921.53–8438.95) compared to no liver disease.

Conclusion

In geriatric hip fracture patients undergoing surgical repair, non-cirrhotic chronic liver disease and cirrhosis independently predict non-routine discharge, acute kidney injury, prolonged LOS and greater hospital costs, and cirrhosis is also significantly associated with greater risk of any complication and in-hospital mortality.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-02832-y.

Defects in energy metabolism are associated with functional exhaustion of bone marrow mesenchymal stem cells in cirrhosis

OBJECTIVES

Cellular and functional exhaustion of bone marrow mesenchymal stem cells (BM-MSC) is significantly associated with the loss of HSCs and hepatic osteodystrophy in cirrhosis. The molecular mechanisms underlying the dysfunction of BM-MSCs are not well understood. We investigated the underlying mechanisms of cellular and functional exhaustion of BM-MSCs in cirrhosis.

METHODS

The MSCs were isolated retrospectively from bone marrow of decompensated alcoholic cirrhosis patients {(Trial registration: ClinicalTrials.gov NCT01902511) (n=10; MELD=16.2±2.3; CTP=8.7±2.3)} and age and gender-matched healthy controls (n=8). Global gene expression profile of healthy bone marrow MSCs (hBM-MSCs) and cirrhosis patients BM-MSCs (cBM-MSCs) were done by mRNA sequencing. XFe24-bioanalyzer analyzed the bioenergetic potential of cells. Level of different cytokines and growth factors in BM-plasma and MSCs secretome were analyzed by Luminex-based bead array.

RESULTS

Analysis of differentially expressed genes showed significant (P<0.01) up-regulation of genes associated with ubiquitination and catabolism of proteins; TNF signaling, insulin resistance, and down-regulation of genes associated with DNA repair, protein processing, cell cycle, and mitochondrial respiration in cBM-MSCs in comparison to hBM-MSCs. Compared to hBM-MSCs, cBM-MSCs showed a significant defect in glycolysis due to insulin resistance and poor glucose uptake (P=0.002). This led to compromised self-renewal capacity and cellular loss of MSCs in cirrhosis. cBM-MSCs also showed a significant impairment in Oxidative phosphorylation (OXPHOS) due to mitochondrial dysfunction leading to defects in the osteogenic differentiation with early aging and senescence.

CONCLUSION

Compromised energy metabolism due to inflammatory and metabolic stress-induced insulin resistance underlies the cellular and functional exhaustion of BM-MSCs in cirrhosis.

Clinical Usefulness of FRAX Score for Predicting Sarcopenia in Patients with Chronic Liver Disease

We investigated the usefulness of the Fracture Risk Assessment tool (FRAX) for predicting sarcopenia in chronic liver disease (CLD). In this cross-sectional study, we evaluated 321 patients with CLD. The FRAX with and without bone mineral density (BMD) was employed to calculate the 10-year risks of major osteoporotic and hip fractures. The FRAX score for high fracture risk was defined as a 10-year major osteoporotic fracture probability of ≥20% or a 10-year hip fracture probability of ≥3%. The diagnosis of sarcopenia was based on the Japan Society of Hepatology criteria. According to the FRAX, with and without BMD, 134 (41.7%) and 193 (60.1%) patients had a high fracture risk, respectively. The high fracture risk group had a significantly higher frequency of sarcopenia than the non-high fracture risk group. FRAX scores of major osteoporotic and hip fractures were negatively correlated with handgrip strength and muscle mass. Using the FRAX with BMD, the cutoff scores of major osteoporotic and hip fractures for predicting sarcopenia were 8.55% (sensitivity/specificity, 0.847/0.568) and 3.35% (0.729/0.746), respectively. Using the FRAX without BMD, they were 18.5% (0.635/0.725) and 7.65% (0.729/0.758), respectively. The FRAX is a simple and convenient screening tool for predicting sarcopenia in patients with CLD.

Aging and direct medical costs of osteoporotic fractures

INTRODUCTION

This study estimated the direct medical costs of osteoporotic fractures from a large claims database in Korea.

MATERIALS AND METHODS

We compared the medical costs of hip, vertebral, and wrist fractures between two age groups (50-64 years vs 65 years and older). We used a generalized linear model to investigate the drivers of osteoporotic fracture medical costs.

RESULTS

Hip fractures had the highest costs, regardless of age, followed by vertebral and wrist. The cost of hip fracture was USD 7285 for those aged 65 years and over and USD 6589 for those aged 50-64 years. The length of hospital days was higher in hip fracture patients, regardless of age, followed by vertebral and wrist. As the number of hospitalizations increased, the medical cost increased by 33.0% (p < 0.0001). Patients older than 65 years who were hospitalized for a fracture had a longer total length of hospital stay, compared to patients aged 50-64, regardlessness of the site of the fracture. The cost of treating fractures among those 65 years and older increased by 31.8% compared to those 50-64 years old (p < 0.0001). The direct medical costs increased by 8.6% as the number of fractures increased (p = 0.041).

CONCLUSIONS

We identified that osteoporotic fracture-related medical costs and hospitalization days increased with age. Interventions are effective in reducing fracture risk the potential to yield substantial cost savings.

Insulin-like growth factor-1 positively associated with bone formation markers and creatine kinase in adults with general physical activity

BACKGROUND

The Insulin-like growth factor-1 (IGF-1) is primarily synthesized by hepatocytes in a growth hormone (GH)-dependent manner, it is also produced by bone and muscle. The effects of exercise on the associations between IGF-1 levels and bone turnover markers (BTM) were found in the previous studies. However, the associations between the levels of IGF-1 and BTM, liver function tests, and skeletal muscle markers in adults with general physical activity were not clear.

METHODS

Ninety-four participants were recruited from healthy survey. Blood samples were collected to analyze the levels of IGF-1, total protein (TP), albumin (Alb), total bilirubin (T-Bil), direct bilirubin (D-Bil), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), bone alkaline phosphatase (BALP), lactate dehydrogenase (LDH), creatine kinase (CK), creatinine (CRTN), and glucose. Urine samples were collected to analyze the CRTN and deoxypyridinoline (Dpd) levels.

RESULTS

The positively significant associations were found between the IGF-1 levels and the levels of ALP, BALP, and CK, respectively. No significant associations were found between the IGF-1 levels and the levels of TP, Alb, A/G, T-Bil, D-Bil, AST, ALT, LDH, glucose, urinary CRTN, urinary Dpd, and Dpd/CRTN ratios, respectively.

CONCLUSION

The serum IGF-1 levels associated with the levels of skeletal muscle and bone formation markers (BFM), not the bone resorption markers under general physical activity in the healthy adults. The physician needs to consider the effects of bone formation and skeletal muscle markers on the IGF-1 levels in the management of IGF-1-related disorders.

Determining Bone Turnover Status in Patients With Chronic Liver Disease

Introduction Hepatic osteodystrophy is an osteoporotic bone disease that occurs in chronic liver disease patients. The global prevalence of osteoporosis in patients with chronic liver disease is 30% to 40%. The pathogenesis of hepatic bone disease is not clear, but it occurs due to unstable bone remodeling with increased bone resorption and decreases bone formation. There has been an interest in determining the clinical utility of bone turnover markers (BTMs) in the assessment of osteoporosis in chronic liver patients. Methods This was a cross-sectional study conducted in patients with chronic liver disease at the section of chemical pathology, department of pathology and laboratory medicine, Aga Khan University (AKU). A total of 50 patients with age >8 years and a history of liver disease >6 months were recruited from January to October 2019. Liver function tests, i.e. aspartate aminotransferase (AST), alanine transaminase (ALT), albumin, and bilirubin, along with clinical signs of liver disease chronicity, were noted. The samples for BTMs, i.e. total serum alkaline phosphatase (ALP) and serum C-terminal telopeptide of type-1 collagen (CTX) were withdrawn and analyzed on Microlab (ELItech Group, Puteaux, France) and ADVIA Centaur (Siemens Diagnostics, NY), respectively. Results The majority of patients were males (n=34, 68%). Twenty-four (48%) patients suffered from fibrosis while 26 (52%) were without fibrosis. Median platelet count (68×109/L (102.5-50)) and median cholesterol levels (102.5 mg/dl (147-99.5)) were decreased, whereas gamma-glutamyl transferase (GGT) levels were higher in the fibrosis group as compared to the non-fibrosis group. The median levels of total ALP were 91.5 IU/L (103-82), and the median levels of CTX were 0.24 pg/ml (0.34-0.21). Conclusion In the present study, no significant difference was found in the BTMs of patients with and without chronic liver disease (CLD). However, there was a positive and significant correlation of BTMs, particularly CTX with age, bilirubin levels, and hepatomegaly.

Micronutrient Deficiencies in Patients with Decompensated Liver Cirrhosis

Patients with cirrhosis often develop malnutrition and micronutrient deficiencies, leading to a worse prognosis and increased mortality. Our main goal was to assess the prevalence of micronutrient deficiencies in patients with decompensated cirrhosis. This was a prospective single-center study including 125 consecutive patients hospitalized for acute decompensation of cirrhosis (mostly of alcoholic etiology). A blood test including trace elements and vitamins was performed on admission. The main micronutrient deficiencies observed were vitamin D (in 94.5%), vitamin A (93.5%), vitamin B6 (60.8%) and zinc (85.6%). Patients in Child-Pugh class C had lower levels of vitamin A (p < 0.0001), vitamin E (p = 0.01) and zinc (p < 0.001), and higher levels of ferritin (p = 0.002) and vitamin B12 (p < 0.001) than those in Child-Pugh class A and B. Patients with a higher model of end-stage liver disease (MELD) score had lower levels of vitamin A (p < 0.0001), vitamin E (p < 0.001), magnesium (p = 0.01) and zinc (p = 0.001), and higher levels of ferritin (p = 0.002) and vitamin B12 (p < 0.0001). Severe hepatic insufficiency correlated with lower levels of zinc, vitamin E and vitamin A, and higher levels of vitamin B12 and ferritin.

Plasma pentosidine levels are associated with prevalent fractures in patients with chronic liver disease

Aim

Osteoporotic fractures negatively impact health-related quality of life and prognosis. Advanced glycation end products (AGEs) impair bone quality and reduce bone strength. The aim of this study was to determine the relationship between plasma levels of pentosidine, a surrogate marker for AGEs, and prevalent fractures in patients with chronic liver disease (CLD).

Methods

This cross-sectional study included 324 patients with CLD. Vertebral fractures were evaluated using lateral thoracolumbar spine radiographs. Information on prevalent fractures was obtained through a medical interview, medical records, and/or radiography. The patients were classified into low (L), intermediate (I), and high (H) pentosidine (Pen) groups based on baseline plasma pentosidine levels.

Results

Of the 324 patients, 105 (32.4%) had prevalent fractures. The prevalence of liver cirrhosis (LC) and prevalent fractures significantly increased stepwise with elevated pentosidine levels. The H-Pen group had the highest prevalence of LC (88.6%, p < 0.001) and prevalent fractures (44.3%, p = 0.007), whereas the L-Pen group had the lowest prevalence of LC (32.1%, p < 0.001) and prevalent fractures (21.0%, p = 0.007). Multiple logistic regression analysis identified pentosidine as a significant independent factor related to prevalent fractures (odds ratio = 1.069, p < 0.001). Pentosidine levels increased stepwise and correlated with liver disease severity. They were markedly high in patients with decompensated LC. In multiple regression analysis, liver functional reserve factors (total bilirubin, albumin, and prothrombin time-international normalized ratio) significantly and independently correlated with pentosidine levels.

Conclusions

Plasma pentosidine was significantly associated with prevalent fractures and liver functional reserve in patients with CLD. Pentosidine may be useful in predicting fracture risk and should be closely followed in CLD patients with advanced disease.

An Overview of the Molecular Mechanisms Contributing to Musculoskeletal Disorders in Chronic Liver Disease: Osteoporosis, Sarcopenia, and Osteoporotic Sarcopenia

The prevalence of osteoporosis and sarcopenia is significantly higher in patients with liver disease than in those without liver disease and osteoporosis and sarcopenia negatively influence morbidity and mortality in liver disease, yet these musculoskeletal disorders are frequently overlooked in clinical practice for patients with chronic liver disease. The objective of this review is to provide a comprehensive understanding of the molecular mechanisms of musculoskeletal disorders accompanying the pathogenesis of liver disease. The increased bone resorption through the receptor activator of nuclear factor kappa (RANK)-RANK ligand (RANKL)-osteoprotegerin (OPG) system and upregulation of inflammatory cytokines and decreased bone formation through increased bilirubin and sclerostin and lower insulin-like growth factor-1 are important mechanisms for osteoporosis in patients with liver disease. Sarcopenia is associated with insulin resistance and obesity in non-alcoholic fatty liver disease, whereas hyperammonemia, low amount of branched chain amino acids, and hypogonadism contributes to sarcopenia in liver cirrhosis. The bidirectional crosstalk between muscle and bone through myostatin, irisin, β-aminoisobutyric acid (BAIBA), osteocalcin, as well as the activation of the RANK and the Wnt/β-catenin pathways are associated with osteosarcopenia. The increased understandings for these musculoskeletal disorders would be contributes to the development of effective therapies targeting the pathophysiological mechanism involved.

Low Serum 25-Hydroxyvitamin D Levels Are Related to Frailty and Sarcopenia in Patients with Chronic Liver Disease

Low vitamin D status is related to frailty and/or sarcopenia in elderly individuals. However, these relationships are unclear in patients with chronic liver disease (CLD). This study aimed at exploring the relationship between serum 25-hydroxyvitamin D [25(OH)D] levels and frailty or sarcopenia in 231 patients with CLD. Frailty was determined based on five factors (weight loss, low physical activity, weakness, slowness, and exhaustion). Sarcopenia was diagnosed by applying the Japan Society of Hepatology criteria. The patients were classified into three groups according to baseline 25(OH)D levels: low (L), intermediate (I), and high (H) vitamin D (VD) groups. Of the 231 patients, 70 (30.3%) and 66 (28.6%) had frailty and sarcopenia, respectively. The prevalence rate of frailty and sarcopenia significantly increased stepwise with a decline in the vitamin D status. The L-VD group showed the highest prevalence rates of frailty and sarcopenia (49.1% (28/57), p < 0.001 for both), whereas the H-VD group showed the lowest prevalence rates of frailty (15.3% (9/59)) and sarcopenia (18.6% (11/59)) (p < 0.001 for both). Multivariate analysis identified serum 25(OH)D levels as a significant independent factor related to frailty and sarcopenia. Serum 25(OH)D levels significantly correlated with handgrip strength, skeletal muscle mass index, and gait speed. In conclusion, low serum vitamin D level, especially severe vitamin D deficient status, is closely related to frailty and sarcopenia in patients with CLD.

Association between osteoporosis and hepatitis B cirrhosis: a case-control study

Background and aims

Hepatitis B virus (HBV)-related cirrhosis is associated with decreased bone mineral density (BMD); however, the mechanism is yet unknown. To assess the incidence of osteoporosis in patients with HBV-associated cirrhosis and relevant mechanisms.

Methods

A total of 80 hospitalized patients with HBV-associated cirrhosis and 80 healthy controls were enrolled. The levels of serum osteocalcin, total procollagen type 1 amino-terminal propeptide, β-C-terminal telopeptide of type I collagen (β-CTX), and 25-hydroxy vitamin D3 (25(OH)D3) was evaluated in the cirrhosis group.

Results

The BMDs of the lumbar spine (P<0.001) and hip joints (P=0.015) in the cirrhosis group were significantly lower than those in the controls. The incidence of osteoporosis in the cirrhosis group was significantly higher than that in the control group (P<0.001). Compared to the patients of the Child-Pugh grade A and B, the BMD of lumbar spine and 25(OH)D3 was significantly decreased in patients of grade C, while β-CTX was elevated. Patients in the cirrhosis group faced a higher risk of osteoporosis as compared to the controls(P<0.001).

Conclusions

Enhanced bone resorption accounted for increased risk of osteoporosis in severe cirrhosis. Thus, HBV-associated cirrhosis was a risk factor for osteoporosis.

Antagonistic Impact of Acrylamide and Ethanol on Biochemical and Morphological Parameters Consistent with Bone Health in Mice

Simple Summary

Alcohol consumption, the drinking of beverages containing ethanol, represents a growing problem worldwide. Alcohol intake is often combined with an improper diet based on highly processed starch products that are rich in acrylamide. Both acrylamide and alcohol have a harmful impact on bone health. We previously demonstrated that adverse effects of ethanol on cortical bone structure were partly reduced by a relatively high dose of acrylamide in mice after one remodelling cycle. The present research was designated to reveal whether the antagonistic impact of both aforementioned toxins can also be achieved using a lower dose of acrylamide. According to our results, individual administrations of acrylamide and ethanol had adverse impacts on biochemical and morphological parameters consistent with bone health in mice. However, the most detrimental effects of ethanol were again alleviated by acrylamide at the dose used in this study.

Abstract

The aim of present study was to verify antagonistic effect of acrylamide (AA) and ethanol (Et) on bone quality parameters. Adult mice (n = 20) were segregated into four groups following 2 weeks administration of toxins: group E1, which received AA (20 mg/kg body weight daily); group E2, which received 15% Et (1.7 g 100% Et/kg body weight daily); group E12, which received simultaneously both toxins; and a control group. An insignificant impact of individual applications of AA, Et or their simultaneous supplementation on the total body weight of mice and the length and weight of their femoral bones was identified. In group E1, higher levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), a decreased level of glutathione (GSH) and elevated endocortical bone remodelling were determined. A significantly lower relative volume of cortical bone, bone mineral density (BMD), elevated endocortical bone remodelling and cortical porosity, higher levels of ALT, AST, lower values for total proteins (TP), GSH, alkaline phosphatase (ALP), calcium, and phosphorus were recorded in group E2. In the mice from group E12, the highest endocortical bone remodelling, decreased values for BMD, TP, GSH and ALP and increased levels of ALT and AST were found. Our findings confirmed the antagonistic impact of AA and Et at doses used in this study on biochemical and morphological parameters consistent with bone health in an animal model.

Chronic Liver Disease and the Risk of Osteoporotic Fractures: A Meta-Analysis

Introduction

Chronic liver disease (CLD) causes more than 1 million deaths every year and remains a pandemic in the last decade affecting more than 600,000 patients in the United States. Previous studies found patients with CLD had increased risk of osteoporosis, so fractures were inferred to be complications of this condition. The aim of this meta-analysis is to summarize the best evidence that correlates CLD patients and the risk to develop osteoporotic fractures versus control patients without CLD.

Methods

A review of the literature using MEDLINE and EMBASE database was performed during December 2017. We included cross-sectional and cohort studies that reported relative risks (RR), odds ratios (OR) and hazard ratios (HR) comparing the risk of developing osteoporotic fractures among patients with CLD versus patients without CLD. Pooled OR and 95% confidence interval (CI) were calculated using generic inverse- variance method. The Newcastle-Ottawa scale was used to determine the quality of the studies. Effect estimates from the individual study were extracted and combined using the random-effect, generic inverse variance method of DerSimonian and Laird. 

Results

After the review of the literature, seven studies fulfilled the eligibility criteria established during the analysis. Significant association was found between CLD and osteoporotic fractures with a pooled OR of 2.13 (95% CI, 1.79 - 2.52). High heterogeneity among the studies was found (I2=88.5). No publication bias was found using Egger regression test (p=0.44).

Conclusion

We found a significant association between CLD and the risk of developing osteoporotic fractures. The calculated risk was 2.13 times higher for patients with CLD when compared with controls. The results showed high heterogeneity but no publication bias. More prospective studies are needed to fully understand the mechanisms involved in loss of bone density and osteoporotic fractures in order to improve the morbidity associated with this disease. 

Nutritional Challenges in Patients with Advanced Liver Cirrhosis

Patients with advanced liver cirrhosis are at risk of malnutrition and nutrition-associated complications. Significant ascites, a frequent finding in these patients, has an especially negative impact on oral nutrition. A negative caloric and protein balance can further deteriorate the already impaired synthetic function of the cirrhotic liver. An important factor in this situation is the diminished capacity of glycogen production and storage in the cirrhotic liver and, consequently, a reduced tolerability for fasting episodes. These episodes are frequently observed in hospitalized patients, e.g., while waiting for investigations, interventions or surgery. A comprehensive work-up of patients with advanced liver cirrhosis should include not only a thorough assessment regarding nutritional deficits, but also a muscularity analysis to identify patients with sarcopenia. The overall nutritional treatment goal is to cover caloric deficits and assure a sufficiently high protein intake. Furthermore, vitamin and micronutrient deficiencies should be identified and corrective measures implemented where required. Ideally, optimal nutrition management can not only prevent the progression of malnutrition and sarcopenia in patients with advanced liver cirrhosis, but positively influence the evolution of the liver disease.

Bone Diseases in Patients with Chronic Liver Disease

Osteoporosis is a frequently observed complication in patients with chronic liver disease, particularly liver cirrhosis and cholestatic liver diseases. In addition, osteoporosis is critical in patients receiving a liver transplant. Nevertheless, few studies have evaluated bone diseases in patients with more frequently observed chronic liver disease, such as chronic viral hepatitis, nonalcoholic fatty liver disease and alcoholic liver disease. Osteoporosis is a disease caused by an imbalance in the activities of osteoblasts and osteoclasts. Over the last few decades, many advances have improved our knowledge of the pathogenesis of osteoporosis. Importantly, activated immune cells affect the progression of osteoporosis, and chronic inflammation may exert an additional effect on the existing pathophysiology of osteoporosis. The microbiota of the intestinal tract may also affect the progression of bone loss in patients with chronic liver disease. Recently, studies regarding the effects of chronic inflammation on dysbiosis in bone diseases have been conducted. However, mechanisms underlying osteoporosis in patients with chronic liver disease are complex and precise mechanisms remain unknown. The following special considerations in patients with chronic liver disease are reviewed: bone diseases in patients who underwent a liver transplant, the association between chronic hepatitis B virus infection treatment and bone diseases, the association between sarcopenia and bone diseases in patients with chronic liver disease, and the association between chronic liver disease and avascular necrosis of the hip. Few guidelines are currently available for the management of low bone mineral density or bone diseases in patients with chronic liver disease. Due to increased life expectancy and therapeutic advances in chronic liver disease, the importance of managing osteoporosis and other bone diseases in patients with chronic liver disease is expected to increase. Consequently, specific guidelines need to be established in the near future.

Single and simultaneous effects of acrylamide and ethanol on bone microstructure of mice after one remodeling cycle

Background

This study aimed to examine femoral bone microstructure of mice after single and simultaneous administration to acrylamide and ethanol since both substances are often consumed separately and/or together by humans. Interactive effects of these toxins were analysed after one remodeling cycle.

Methods

Twenty clinically healthy adult mice were randomly divided into four groups following 2 weeks administration of toxins: A group - mice were fed with acrylamide (40 mg/kg bw); E group - mice were ethanol-fed (15% ethanol); AE group - mice were simultaneously fed with both toxins, and a C group – control (without acrylamide and/or ethanol supplementation). Generally, 2D and 3D imaging methods were used to determine cortical and trabecular bone tissues microstructure. Biochemical analyses of plasma parameters were also realized using commercially available ELISA tests and spectrophotometrically.

Results

Single and simultaneous exposure to acrylamide and ethanol affected only cortical bone microstructure. No significant changes in trabecular bone morphometry were detected among all groups. In mice from the A group, increased endocortical remodeling associated with a higher level of serum calcium and vasoconstriction of primary osteon’s vascular canals (POVC) were identified. On the contrary, increased cortical porosity consistent with a decreased relative bone volume, bone mineral density (BMD) and lower levels of alkaline phosphatase (ALP), glutathione (GSH), calcium in plasma and also with vasodilation of POVC were observed in the E group. In the AE group, the highest density of secondary osteons associated with a lower BMD and decreased levels of ALP, GSH were documented. The parameters of POVC and Haversian canals approximated to the C group. In addition, single and simultaneous exposure to both toxins caused liver disease consistent with a higher values of alanine aminotransferase (ALT), aspartate aminotransferase (AST) in plasma of all experimental groups.

Conclusions

Single administration to acrylamide and ethanol had negative effects on cortical bone structure of mice after one remodeling cycle. However, we identified possible antagonistic impact of these toxins on the structure of the cortical bone.

Crosssectional Assessment of Bone Mass Density in Adults with Hepatitis B Virus and Hepatitis C Virus Infection

Osteoporosis is one of the major complications in chronic hepatitis B virus (HBV) and hepatitis C (HCV) infection. However, few studies had examined the relationship between hepatic viral infection with bone loss. Our aim was to investigate the association between hepatic viral infection with bone mineral density (BMD) in a cross-sectional study. Participants who attended the health examinations at the Tri-Service General Hospital (TSGH), Taiwan, were enrolled in the study. Diagnosis of viral hepatitis was confirmed by the serum viral markers of hepatitis B surface antigen (HBsAg) and anti-HCV, and BMD measurement was performed by the bone densitometry. Subjects were divided into four groups by the presence of viral markers. The association between hepatic viral infection and BMD was examined by a multivariate linear regression model. HBV infection was inversely associated with BMD after full adjusting with β values of -0.17 (95% CI: -0.29, -0.05) (p < 0.05). The relationship remained significant in males (β = -0.16, 95% CI = -0.31, -0.01) (p < 0.05). In subjects with body mass index less than 30 HBV infection was associated with reduced BMD (β = -0.16, 95% CI = -0.29, -0.02) (p < 0.05). However, HCV infection was only associated with an increase in BMD in patients with BMI less than 30 (β = 0.17, 95% CI = 0.21, 0.32) (p < 0.05). Chronic HBV infection was significantly associated with reduced BMD in males. The impact of viral hepatitis on bone health deserves further investigation for the potential pathophysiological mechanisms.

Suboptimal Level of Bone-Forming Cells in Advanced Cirrhosis are Associated with Hepatic Osteodystrophy

Bone loss is common in advanced cirrhosis, although the precise mechanisms underlying bone loss in cirrhosis are unknown. We studied the profile and functionality of bone-forming cells and bone-building proteins in bone marrow (BM) of individuals with cirrhosis (n = 61) and individuals without cirrhosis as normal controls (n = 50). We also performed dual energy X-ray absorptiometry for clinical correlation. BM mesenchymal cells (MSCs) were analyzed for colony-forming units-fibroblasts and their osteogenic (fibronectin-1 [FN1], insulin-like growth factor binding protein 3 [IGFBP3], collagen type 1 alpha 1 chain [COL1A1], runt-related transcription factor 2 [RUNX2], and alkaline phosphatase, liver [ALPL]) and adipogenic ( adiponectin, C1Q, and collagen domain containing [ADIPOQ], peroxisome proliferator-activated receptor gamma [PPARγ], and fatty acid binding protein 4 [FABP4]) potentials. Colony-forming units-fibroblasts were lower in patients with cirrhosis (P = 0.002) than in controls. Cirrhotic BM-MSCs showed >2-fold decrease in osteogenic markers. Compared to controls, patients with cirrhosis showed fewer osteocytes (P = 0.05), osteoblasts, chondroblasts, osteocalcin-positive (osteocalcin+) area, clusters of differentiation (CD)169+ macrophages (P < 0.001, each), and nestin+ MSCs (P = 0.001); this was more apparent in Child-Turcotte-Pugh (CTP) class C than A (P < 0.001). Multivariate logistic regression showed low nestin+ MSCs (P = 0.004) as a predictor of bone loss. Bone-resolving osteoclasts were comparable among CTP groups, but >2-fold decreased anti-osteoclastic and increased pro-osteoclastic factors were noted in patients with CTP C compared to CTP A. Bone-building proteins (osteocalcin [P = 0.008], osteonectin [P < 0.001], and bone morphogenic protein 2 [P = 0.001]) were decreased while anti-bone repair factors (fibroblast growth factor 23 [P = 0.015] and dipeptidyl peptidase 4 [P < 0.001]) were increased in BM and peripheral blood; this was more apparent in advanced cirrhosis. The dual energy X-ray absorptiometry scan T score significantly correlated with the population of osteoblasts, osteocytes, MSCs, and CD169+ macrophages. Conclusion: Osteoprogenitor cells are substantially reduced in patients with cirrhosis and more so in advanced disease. Additionally, increased anti-bone repair proteins enhance the ineffective bone repair and development of osteoporosis in cirrhosis. Hepatology Communications 2018;0:0-0).

Liver disease and mortality among patients with hip fracture: a population-based cohort study

Purpose

The aim of this study was to examine the prognostic impact of liver disease on mortality following hip fracture (HF).

Patients and methods

This nationwide cohort study, based on prospectively collected data retrieved from Danish registries, included all patients diagnosed with incident HF in Denmark during 1996-2013. Patients were classified based on the coexisting liver disease at the time of HF, ie, no liver disease, noncirrhotic liver disease, and liver cirrhosis. We computed 30-day and 31-365-day mortality risks. To compare patients with and without liver disease, we computed mortality adjusted hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) using Cox regression controlled for potential confounders.

Results

Among 152,180 HF patients, 2,552 (1.7%) patients had noncirrhotic liver disease and 1,866 (1.2%) patients had liver cirrhosis. Thirty-day mortality was 9.4% among patients with noncirrhotic liver disease, 12.6% among patients with liver cirrhosis patients, and 9.7% among patients without liver disease. Compared to patients without liver disease, crude and adjusted HRs within 30 days following HF were, respectively, 0.96 (95% CI: 0.85-1.10) and 1.24 (95% CI: 1.09-1.41) for patients with noncirrhotic liver disease and 1.30 (95% CI: 1.14-1.48) and 2.25 (95% CI: 1.96-2.59) for those with liver cirrhosis. Among patients who survived 30 days post-HF, the 31-365-day mortality was 18.5% among patients with noncirrhotic liver disease, 26.4% among patients with liver cirrhosis, and 19.4% among patients without liver disease. Corresponding crude and adjusted HRs were, respectively, 0.95 (95% CI: 0.86-1.04) and 1.08 (95% CI: 0.99-1.20) for patients with noncirrhotic liver disease and 1.40 (95% CI: 1.27-1.54) and 1.91 (95% CI: 1.72-2.12) for those with liver cirrhosis.

Conclusion

Liver disease patients, especially those with liver cirrhosis, had increased 30-day mortality and 31-365-day mortality following HF, compared to patients without liver disease.

Pharmaceutical iron formulations do not cross a model of the human blood-brain barrier

Whether iron formulations used therapeutically for a variety of conditions involving iron deficiency can deliver iron to the brain is a significant clinical question given the impact that iron loading has on the brain in neurodegenerative diseases. In this study, we examine the ability of 5 pharmaceutical iron formulations that are given intravenously for treatment of iron deficiency to cross an in vitro model of the blood-brain barrier. The model uses human brain endothelial cells derived from induced pluripotent stem cells. We report that, compared to the natural iron delivery proteins, transferrin and H-ferritin, the pharmaceutical iron formulations neither cross the blood-brain barrier model nor significantly load the endothelial cells with iron. Furthermore, we report that mimicking brain iron sufficiency or deficiency by exposing the endothelial cells to apo- or holo-transferrin does not alter the amount of iron compound transported by or loaded into the cells. Coupled with previous studies, we propose that pharmaceutical iron formulations must first be processed in macrophages to make iron bioavailable. The results of this study have significant clinical and mechanistic implications for the use of therapeutic iron formulations.

Association between pre-sarcopenia, sarcopenia, and bone mineral density in patients with chronic hepatitis C

BACKGROUND

Preserved skeletal muscle is essential for the maintenance of healthy bone. Loss of bone mineral density (BMD) and muscle strength, considered a predictor of BMD, have been demonstrated in patients with cirrhosis, but they are poorly studied in chronic hepatitis C (CHC) without cirrhosis. Thus, we aimed to evaluate the prevalence of low BMD and its association with body composition, muscle strength, and nutritional status in CHC.

METHODS

One hundred and four subjects [mean age, 50.5 ± 11.3 years; 75.0% males; 67.3% non-cirrhotic; and 32.7% with compensated cirrhosis] with CHC, prospectively, underwent scanning of the lean tissue, appendicular skeletal muscle mass (ASM), fat mass, lumbar spine, hip, femoral neck, and whole-body BMD by dual-energy X-ray absorptiometry. Muscle strength was assessed by dynamometry. Sarcopenia was defined by the presence of both low, ASM/height2 (ASMI) and low muscle strength according to the European Working Group on Sarcopenia in Older People criteria. The cut-off points for low ASMI and low muscle strength, for women and men, were < 5.45 and < 7.26 kg/m2 and < 20 and < 30 kg, respectively. According to the adopted World Health Organization criteria in men aged > 50 years, the T-score of osteopenia is between -1.0 and -2.49 standard deviation (SD) below the young average value and of osteoporosis is ≥-2.5 SD below the young normal mean for men, and the Z-score of low bone mass is ≤-2.0 SD below the expected range in men aged < 50 years and women in the menacme. Nutritional status evaluation was based on the Controlling Nutritional Status score.

RESULTS

Low BMD, low muscle strength, pre-sarcopenia, sarcopenia, and sarcopenic obesity were observed in 34.6% (36/104), 27.9% (29/104), 14.4% (15/104), 8.7% (9/104), and 3.8% (4/104) of the patients, respectively. ASMI was an independent predictor of BMD (P < 0.001). Sarcopenia was independently associated with bone mineral content (P = 0.02) and malnutrition (P = 0.01). In 88.9% of the sarcopenic patients and in all with sarcopenic obesity, BMI was normal. The mid-arm muscle circumference was positively correlated with ASMI (r = 0.88; P < 0.001).

CONCLUSIONS

This is the first study to demonstrate that ASM is an independent predictor of BMD in CHC. Mid-arm muscle circumference coupled with handgrip strength testing should be incorporated into routine clinical practice to detect low muscle mass, which may be underdiagnosed when only BMI is used. These findings may influence clinical decision-making and contribute to the development of effective strategies to screen the musculoskeletal abnormalities in CHC patients, independently of the stage of the liver disease.

Bone mineral density loss in patients with cirrhosis

BACKGROUND/AIMS

Evidence of increased risk of osteoporosis and osteopenia in chronic liver disease and cirrhosis is inconsistent. This study aims to investigate this relationship and to identify the predictors of increased loss of bone mineral density in Saudi patients.

PATIENTS AND METHODS

One hundred and sixty-four patients and controls who are age and gender matched, were included in this study with 1:1 ratio. Patients' included in this study were adults with confirmed liver cirrhosis. Bone mineral densitometry (BMD) at both lumbar spine (LS) and femoral neck (FN) were collected for both groups. Univariate and multivariate regression analyses were performed to identify predictors of BMD loss.

RESULTS

Results showed that cirrhotic patients are at higher risk of developing osteoporosis or osteopenia at LS (OR 2.23, 95% CI [1.19-4.19], P = 0.01) but not at FN, when compared to control sample. Patients with cirrhosis were found to have lower vitamin D and PTH levels (P = 0.0005) and (P = 0.006), respectively. Of the possible predictors tested (gender, age, body mass index [BMI], phosphorus, calcium, parathyroid hormone (PTH), vitamin D, and Model for End Stage Liver Disease [MELD] score), female gender was the main predictor of loss of BMD at LS only (OR 4.80, 95% CI [1.47-15.73], P = 0.01).

CONCLUSIONS

The study showed that cirrhotic patients are at increased susceptibility of having decreased BMD, particularly at the LS and it highlights the need for preventive measures, especially for female patients.

Significant liver fibrosis assessed using liver transient elastography is independently associated with low bone mineral density in patients with non-alcoholic fatty liver disease

Background

Metabolic bone disorders frequently occur in patients with chronic liver disease; however, the association between liver fibrosis and bone mineral density in patients with non-alcoholic fatty liver disease (NAFLD) is unclear.

Methods

This is a cross-sectional analysis of 231 asymptomatic subjects (160 women, 61.6 years old) from a university hospital setting, between February 2012 and December 2014. Bone mineral density (BMD) was measured at the lumbar spine, femur neck, and total hip using dual-energy X-ray absorptiometry (DXA). Liver fibrosis and steatosis were assessed using transient elastography.

Results

Among a total of 231 individuals, 129 subjects (55.8%) had NAFLD. BMDs at lumbar spine, femur neck, and total hip were significantly lower in patients having NAFLD with significant fibrosis, compared with patients having NAFLD without significant fibrosis (Ps<0.005). In patients with NAFLD, significant liver fibrosis revealed marked negative correlations with BMD at the lumber spine (r = –0.19, P = 0.032), femur neck (r = –0.19, P = 0.034), and total hip (r = –0.21, P = 0.016). A multivariate linear regression analysis revealed that significant liver fibrosis was independently correlated with low BMD at the femur neck (β = –0.18, P = 0.039) and total hip (β = –0.21, P = 0.005) after adjustment for age, sex, BMI, fasting plasma glucose, alanine aminotransferase, high-density lipoprotein cholesterol, and liver steatosis among patients with NAFLD. Using multivariable logistic regression, significant liver fibrosis was independently associated with overall osteopenia and osteoporosis in subjects having NAFLD (OR = 4.10, 95% CI = 1.02–16.45).

Conclusion

The presence of significant liver fibrosis assessed via TE was independently associated with low BMD in NAFLD subjects.

Hepatitis C virus infection and risk of osteoporosis: A meta-analysis

BACKGROUND/AIMS

Hepatitis C virus (HCV) infection is one of the most common infections worldwide. Several epidemiologic studies have suggested that patients with HCV infection might be at an increased risk of osteoporosis. However, the data on this relationship remains inconclusive. This meta-analysis was conducted with the aim to summarize all available evidence.

MATERIALS AND METHODS

A literature search was performed using MEDLINE and EMBASE databases from inception to June 2016. Studies that reported relative risks, odd ratios (OR), or hazard ratios comparing the risk of osteoporosis among HCV-infected patients versus those without HCV infection were included. Pooled OR and 95% confidence interval (CI) were calculated using a random-effect, generic inverse variance method.

RESULTS

Four studies met our eligibility criteria and were included in the analysis. We found a higher risk of osteoporosis among patients with chronic HCV with OR of 1.65 (95% CI: 0.98-2.77). Sensitivity analysis including only studies with higher quality yielded a higher OR, and the result was statistically significant (OR: 2.47; 95% CI: 1.03-5.93).

CONCLUSIONS

Our study demonstrated a higher risk of osteoporosis among HCV-infected patients. Further studies are required to clarify how this risk should be addressed in clinical practice.

Osteoporosis in liver disease: pathogenesis and management

Osteoporosis affects a substantial proportion of patients with chronic liver disease. Pathologic fracture in osteoporosis significantly affects quality of life and life expectancy. By some estimates, 40% of patients with chronic liver disease may experience osteoporotic fracture. In this study we review the pathogenesis, diagnosis and treatment of specific liver disease entities and their relation to osteoporosis.

Low Serum Lysosomal Acid Lipase Activity Correlates with Advanced Liver Disease

Fatty liver has become the most common liver disorder and is recognized as a major health burden in the Western world. The causes for disease progression are not fully elucidated but lysosomal impairment is suggested. Here we evaluate a possible role for lysosomal acid lipase (LAL) activity in liver disease. To study LAL levels in patients with microvesicular, idiopathic cirrhosis and nonalcoholic fatty liver disease (NAFLD). Medical records of patients with microvesicular steatosis, cryptogenic cirrhosis and NAFLD, diagnosed on the basis of liver biopsies, were included in the study. Measured serum LAL activity was correlated to clinical, laboratory, imaging and pathological data. No patient exhibited LAL activity compatible with genetic LAL deficiency. However, serum LAL activity inversely predicted liver disease severity. A LAL level of 0.5 was the most sensitive for detecting both histologic and noninvasive markers for disease severity, including lower white blood cell count and calcium, and elevated γ-glutamyltransferase, creatinine, glucose, glycated hemoglobin, uric acid and coagulation function. Serum LAL activity <0.5 indicates severe liver injury in patients with fatty liver and cirrhosis. Further studies should define the direct role of LAL in liver disease severity and consider the possibility of replacement therapy.

Associations with fracture in patients with diabetes: a nested case-control study

OBJECTIVES

Diabetes mellitus is associated with an increased risk of fractures, which is not fully explained by bone mineral density and common risk factors. The aim of this study is to investigate the association of medication and biochemical markers on the risk of fracture in a diabetes population.

DESIGN AND SETTING

A nested case-control study was conducted based on Danish diabetes patients from The Danish National Hospital Discharge Registry.

PARTICIPANTS

The cases of the study were diabetes patients with a fracture (n=24,349), and controls were diabetes patients with no fracture (n=132,349). A total of 2627 diabetes patients were available for an analysis of patient characteristics, comorbidities, biochemical parameters and drug usage.

RESULTS

Age (OR=1.02, 95% CI 1.01 to 1.04), diabetes duration (OR=1.06, 95% CI 1.02 to 1.09), a diagnosis of previous fracture (OR=2.20, 95% CI 1.55 to 3.11), an alcohol-related diagnosis (OR=2.94, 95% CI 1.76 to 4.91), total cholesterol level (OR=2.50, 95% CI 1.20 to 5.21) and the usage of antiepileptics (OR=2.12, 95% CI 1.39 to 3.59) all increased the odds of fracture. Low-density lipoprotein cholesterol levels decreased the odds of fracture (OR =0.34, 95% CI 0.16 to 0.74), where the level of 3.04-5.96 mmol/L was optimal with regard to fracture risk.

CONCLUSIONS

Low-density lipoprotein cholesterol may improve our understanding of fractures in diabetes patients, and it may be added to current fracture risk models in diabetes patients.

Nutrition therapy: Integral part of liver transplant care

Managing malnutrition before liver transplantation (LTx) while on the waiting list and, excessive weight gain/metabolic disturbances in post-surgery are still a challenge in LTx care. The aim of this review is to support an interdisciplinary nutrition approach of these patients. Cirrhotic patients are frequently malnourished before LTx and this is associated with a poor prognosis. Although the relation between nutritional status versus survival, successful operation and recovery after LTx is well established, prevalence of malnutrition before the operation is still very high. Emerging research has also demonstrated that sarcopenia pre and post-transplant is highly prevalent, despite the weight gain in the postoperative period. The diagnosis of the nutritional status is the first step to address the adequate nutritional therapy. Nutritional recommendations and therapy to manage the nutritional status of LTx patients are discussed in this review, regarding counseling on adequate diets and findings of the latest research on using certain immunonutrients in these patients (branched chain amino-acids, pre and probiotics). Nutrition associated complications observed after transplantation is also described. They are commonly related to the adverse effects of immunosuppressive drugs, leading to hyperkalemia, hyperglycemia and weight gain. Excessive weight gain and post-transplant metabolic disorders have long been described in post-LTx and should be addressed in order to reduce associated morbidity and mortality.

Chronic iron deficiency as an emerging risk factor for osteoporosis: a hypothesis

Iron is essential in oxygen transport and participates in many enzymatic systems in the body, with important roles in collagen synthesis and vitamin D metabolism. The relationship between iron and bone health comes from clinical observations in iron overload patients who suffered bone loss. The opposite scenario—whether iron deficiency, with or without anemia, affects bone metabolism—has not been fully addressed. This is of great interest, as this nutrient deficiency is a worldwide public health problem and at the same time osteoporosis and bone alterations are highly prevalent. This review presents current knowledge on nutritional iron deficiency and bone remodeling, the biomarkers to evaluate iron status and bone formation and resorption, and the link between iron and bone metabolism. Finally, it is hypothesized that chronic iron deficiency induces bone resorption and risk of osteoporosis, thus complete recovery from anemia and its prevention should be promoted in order to improve quality of life including bone health. Several mechanisms are suggested; hence, further investigation on the possible impact of chronic iron deficiency on the development of osteoporosis is needed.