Donepezil prevents RANK-induced bone loss via inhibition of osteoclast differentiation by downregulating acetylcholinesterase

Relationship between donepezil and fracture risk in patients with dementia with Lewy bodies

AIM

Patients with dementia with Lewy bodies (DLB) are at a high risk for falls and fractures. Although cholinesterase inhibitors reportedly are effective in suppressing the progression of cognitive symptoms in DLB patients, their effects on fracture risk remain unclarified. This study aimed to evaluate the association between donepezil use and hip fracture risk in older patients with DLB.

METHODS

Using the Japanese insurance claim database, we collected the data of patients aged ≥65 years with DLB from April 2012 to March 2019. After propensity score matching, we compared the fracture rate over 3 years between DLB patients receiving donepezil and those not receiving antidementia drugs.

RESULTS

Altogether, 24 022 239 individuals aged ≥65 years were newly registered from April 2012 to March 2016 and had verifiable information from 6 months before to 3 years after the registration. We identified 6634 pure-DLB patients and analyzed the data of 1182 propensity score-matched pairs. The characteristics, including age, sex, fracture history, osteoporosis, and bone mineral density test rate, of the two groups were well balanced by propensity score matching. The incidence rate of hip fracture was significantly lower in DLB patients receiving donepezil than in those not receiving antidementia drugs (0.60 vs. 1.44/100 person-years, P < 0.001), whereas that of vertebral fractures was the same.

CONCLUSIONS

Donepezil administration in Japanese people aged ≥65 years with DLB was significantly associated with a decreased risk of hip fracture. Donepezil may provide new benefits to DLB patients. Geriatr Gerontol Int 2024; 24: 782-788.

The risk of bone fractures in dementia patients receiving acetylcholinesterase inhibitors: a meta-analysis

Aim

The authors aimed to conduct a meta-analysis to determine if acetylcholinesterase inhibitors may pose a direct threat, increasing the incidence of fractures in dementia patients.

Methods

PubMed, Scopus, and Cochrane Library were searched. Inclusion criteria were any original studies that demonstrated the link between acetylcholinesterase inhibitors and the incidence of fracture in patients with dementia. RevMan(5.4) was used.

Results

Seven observational studies were included. The total number of patients included in the acetylcholinesterase inhibitors group is 274 332 and 290 347 in the control group. The pooled analysis showed that the risk of bone fracture was not statistically different between dementia patients who received acetylcholinesterase inhibitors and those who did not receive them (odds ratio=1.44, CI 0.95, 2.19, P=0.09). Subgroup analysis showed no statistically significant difference between dementia patients who took acetylcholinesterase inhibitors, and those who didn't take acetylcholinesterase inhibitors in those more than or equal to 80 years old and those less than 80 years old (P=0.44) and (P=0.34) respectively. However, our results showed a statistically significant association between dementia patients who received acetylcholinesterase inhibitors and decreased fracture risk in those receiving the treatment for more than or less than 2 years (risk ratio=0.48, CI= 0.45, 0.51, P<0.00001) and (risk ratio=0.84, CI 0.70, 0.99, P=0.04), respectively.

Conclusion

Our study revealed no role for acetylcholinesterase inhibitors in increasing the risk of fracture compared with controls. Hence, based on our analysis, they might have a protective role against fracture when used for long periods considering their positive action on bone growth and development. Therefore, Acetylcholinesterase inhibitors could be considered a safe option for improving cognitive functions in elderly demented patients without carrying any additional risks.

Association Between Persistent Treatment of Alzheimer's Dementia and Osteoporosis Using a Common Data Model

Background and Purpose

As it becomes an aging society, interest in senile diseases is increasing. Alzheimer's dementia (AD) and osteoporosis are representative senile diseases. Various studies have reported that AD and osteoporosis share many risk factors that affect each other's incidence. This aimed to determine if active medication treatment of AD could affect the development of osteoporosis.

Methods

The Health Insurance Review and Assessment Service provided data consisting of diagnosis, demographics, prescription drug, procedures, medical materials, and healthcare resources. In this study, data of all AD patients in South Korea who were registered under the national health insurance system were obtained. The cohort underwent conversion to an Observational Medical Outcomes Partnership-Common Data Model version 5 format.

Results

This study included 11,355 individuals in the good persistent group and an equal number of 11,355 individuals in the poor persistent group from the National Health Claims database for AD drug treatment. In primary analysis, the risk of osteoporosis was significantly higher in the poor persistence group than in the good persistence group (hazard ratio, 1.20 [95% confidence interval, 1.09-1.32]; p<0.001).

Conclusions

We found that the good persistence group treated with anti-dementia drugs for AD was associated with a significant lower risk of osteoporosis in this nationwide study. Further studies are needed to clarify the pathophysiological link in patients with two chronic diseases.

Antidementia medication acetylcholinesterase inhibitors have therapeutic benefits on osteoporotic bone by attenuating osteoclastogenesis and bone resorption

This study was designed to determine whether the use of acetylcholinesterase inhibitors (AChEIs), a group of drugs that stimulate acetylcholine receptors and are used to treat Alzheimer's disease (AD), is associated with osteoporosis protection and inhibition of osteoclast differentiation and function. Firstly, we examined the effects of AChEIs on RANKL-induced osteoclast differentiation and function with osteoclastogenesis and bone resorption assays. Next, we investigated the impacts of AChEIs on RANKL-induced nuclear factor κB and NFATc1 activation and expression of osteoclast marker proteins CA-2, CTSK and NFATc1, and dissected the MAPK signaling in osteoclasts in vitro by using luciferase assay and Western blot. Finally, we assessed the in vivo efficacy of AChEIs using an ovariectomy-induced osteoporosis mouse model, which was analyzed using microcomputed tomography, in vivo osteoclast and osteoblast parameters were assessed using histomorphometry. We found that Donepezil and Rivastigmine inhibited RANKL-induced osteoclastogenesis and impaired osteoclastic bone resorption. Moreover, AChEIs reduced the RANKL-induced transcription of Nfatc1, and expression of osteoclast marker genes to varying degrees (mainly Donepezil and Rivastigmine but not Galantamine). Furthermore, AChEIs variably inhibited RANKL-induced MAPK signaling accompanied by downregulation of AChE transcription. Finally, AChEIs protected against OVX-induced bone loss mainly by inhibiting osteoclast activity. Taken together, AChEIs (mainly Donepezil and Rivastigmine) exerted a positive effect on bone protection by inhibiting osteoclast function through MAPK and NFATc1 signaling pathways through downregulating AChE. Our findings have important clinical implications that elderly patients with dementia who are at risk of developing osteoporosis may potentially benefit from therapy with the AChEI drugs. Our study may influence drug choice in those patients with both AD and osteoporosis.

Effects of Donepezil on the Musculoskeletal System in Female Rats

The extension of human life makes it more and more important to prevent and treat diseases of the elderly, including Alzheimer's disease (AD) and osteoporosis. Little is known about the effects of drugs used in the treatment of AD on the musculoskeletal system. The aim of the present study was to investigate the effects of donepezil, an acetylcholinesterase inhibitor, on the musculoskeletal system in rats with normal and reduced estrogen levels. The study was carried out on four groups of mature female rats: non-ovariectomized (NOVX) control rats, NOVX rats treated with donepezil, ovariectomized (OVX) control rats and OVX rats treated with donepezil. Donepezil (1 mg/kg p.o.) was administered for four weeks, starting one week after the ovariectomy. The serum concentrations of CTX-I, osteocalcin and other biochemical parameters, bone mass, density, mineralization, histomorphometric parameters and mechanical properties, and skeletal muscle mass and strength were examined. Estrogen deficiency increased bone resorption and formation and worsened cancellous bone mechanical properties and histomorphometric parameters. In NOVX rats, donepezil decreased bone volume to tissue volume ratio in the distal femoral metaphysis, increased the serum phosphorus concentration and tended to decrease skeletal muscle strength. No significant bone effects of donepezil were observed in OVX rats. The results of the present study indicate slightly unfavorable effects of donepezil on the musculoskeletal system in rats with normal estrogen levels.

Alzheimer's Disease and Impaired Bone Microarchitecture, Regeneration and Potential Genetic Links

Alzheimer's Disease (AD) and osteoporosis are both age-related degenerative diseases. Many studies indicate that these two diseases share common pathogenesis mechanisms. In this review, the osteoporotic phenotype of AD mouse models was discussed, and shared mechanisms such as hormonal imbalance, genetic factors, similar signaling pathways and impaired neurotransmitters were identified. Moreover, the review provides recent data associated with these two diseases. Furthermore, potential therapeutic approaches targeting both diseases were discussed. Thus, we proposed that preventing bone loss should be one of the most important treatment goals in patients with AD; treatment targeting brain disorders is also beneficial for osteoporosis.

Roles for B[a]P and FICZ in subchondral bone metabolism and experimental temporomandibular joint osteoarthritis via the AhR/Cyp1a1 signaling axis

Bone loss due to smoking represents a major risk factor for fractures and bone osteoporosis. Signaling through the aryl hydrocarbon receptor (AhR) and its ligands contributes to both bone homeostasis and inflammatory diseases. It remains unclear whether the same AhR signaling axis affects the temporomandibular joint (TMJ). The aim of this study was to investigate possible mechanisms which mediate bone loss in the TMJ due to smoking. In particular, whether benzo[a]pyrene (B[a]P), a carcinogen of tobacco smoke, induces expression of the AhR target gene, Cyp1a1, in mandibular condyles. Possible functions of an endogenous ligand of FICZ, were also investigated in a TMJ-osteoarthritis (OA) mouse model. B[a]P was administered orally to wild-type and AhR-/- mice and bone metabolism was subsequently examined. TMJ-OA was induced in wild-type mice with forceful opening of the mouth. Therapeutic functions of FICZ were detected with μCT and histology. Exposure to B[a]P accelerated bone loss in the mandibular subchondral bone. This bone loss manifested with osteoclastic bone resorption and upregulated expression of Cyp1a1 in an AhR-dependent manner. In a mouse model of TMJ-OA, FICZ exhibited a dose-dependent rescue of mandibular subchondral bone loss by repressing osteoclast activity. Meanwhile, in vitro, pre-treatment with FICZ reduced RANKL-mediated osteoclastogenesis. B[a]P regulates mandibular subchondral bone metabolism via the Cyp1a1. The AhR ligand, FICZ, can prevent TMJ-OA by regulating osteoclast differentiation.

Cholinergic System and Its Therapeutic Importance in Inflammation and Autoimmunity

Neurological and immunological signals constitute an extensive regulatory network in our body that maintains physiology and homeostasis. The cholinergic system plays a significant role in neuroimmune communication, transmitting information regarding the peripheral immune status to the central nervous system (CNS) and vice versa. The cholinergic system includes the neurotransmitter\ molecule, acetylcholine (ACh), cholinergic receptors (AChRs), choline acetyltransferase (ChAT) enzyme, and acetylcholinesterase (AChE) enzyme. These molecules are involved in regulating immune response and playing a crucial role in maintaining homeostasis. Most innate and adaptive immune cells respond to neuronal inputs by releasing or expressing these molecules on their surfaces. Dysregulation of this neuroimmune communication may lead to several inflammatory and autoimmune diseases. Several agonists, antagonists, and inhibitors have been developed to target the cholinergic system to control inflammation in different tissues. This review discusses how various molecules of the neuronal and non-neuronal cholinergic system (NNCS) interact with the immune cells. What are the agonists and antagonists that alter the cholinergic system, and how are these molecules modulate inflammation and immunity. Understanding the various functions of pharmacological molecules could help in designing better strategies to control inflammation and autoimmunity.

Non-neuronal Role of Acetylcholinesterase in Bone Development and Degeneration

Acetylcholinesterase (AChE), an enzyme catalyzing the degradation of acetylcholine, plays an important suppressive role in the cholinergic regulation by terminating the action of acetylcholine. The expression of acetylcholinesterase and other cholinergic components is not restricted to only brain and nerve tissues but can also be found in non-neuronal tissues like the immune system and bone tissue. Primary identification of these components has been achieved. However, the information about their specific functions and underlying molecular mechanisms in bone remains scattered. Here, the physiological process of bone development, homeostasis, and degeneration are introduced. Next, the cholinergic system and its expression in bone tissue is documented. Among them, special attention goes to AChE, as the structure of this enzyme suggests diverse binding affinities, enabled by a peripheral site and a catalytic site. The peripheral site supports the non-enzymatic function of AChE in non-neuronal systems. Based on recent studies, the non-neuronal roles of acetylcholinesterase, both enzymatically and non-enzymatically, in bone development, homeostasis and degeneration are summarized briefly together with potential mechanisms to support these functions. We conclude that AChE may be a potential therapeutic target for bone diseases like osteoporosis.

Rps27a might act as a controller of microglia activation in triggering neurodegenerative diseases

Neurodegenerative diseases (NDDs) are increasing serious menaces to human health in the recent years. Despite exhibiting different clinical phenotypes and selective neuronal loss, there are certain common features in these disorders, suggesting the presence of commonly dysregulated pathways. Identifying causal genes and dysregulated pathways can be helpful in providing effective treatment in these diseases. Interestingly, in spite of the considerable researches on NDDs, to the best of our knowledge, no dysregulated genes and/or pathways were reported in common across all the major NDDs so far. In this study, for the first time, we have applied the three-way interaction model, as an approach to unravel sophisticated gene interactions, to trace switch genes and significant pathways that are involved in six major NDDs. Subsequently, a gene regulatory network was constructed to investigate the regulatory communication of statistically significant triplets. Finally, KEGG pathway enrichment analysis was applied to find possible common pathways. Because of the central role of neuroinflammation and immune system responses in both pathogenic and protective mechanisms in the NDDs, we focused on immune genes in this study. Our results suggest that "cytokine-cytokine receptor interaction" pathway is enriched in all of the studied NDDs, while "osteoclast differentiation" and "natural killer cell mediated cytotoxicity" pathways are enriched in five of the NDDs each. The results of this study indicate that three pathways that include "osteoclast differentiation", "natural killer cell mediated cytotoxicity" and "cytokine-cytokine receptor interaction" are common in five, five and six NDDs, respectively. Additionally, our analysis showed that Rps27a as a switch gene, together with the gene pair {Il-18, Cx3cl1} form a statistically significant and biologically relevant triplet in the major NDDs. More specifically, we suggested that Cx3cl1 might act as a potential upstream regulator of Il-18 in microglia activation, and in turn, might be controlled with Rps27a in triggering NDDs.

Brain-Derived Acetylcholine Maintains Peak Bone Mass in Adult Female Mice

Preclinical and clinical data support a role of the sympathetic nervous system in the regulation of bone remodeling, but the contribution of parasympathetic arm of the autonomic nervous system to bone homeostasis remains less studied. In this study, we sought to determine whether acetylcholine (ACh) contributes to the regulation of bone remodeling after peak bone mass acquisition. We show that reduced central ACh synthesis in mice heterozygous for the choline transporter (ChT) leads to a decrease in bone mass in young female mice, thus independently confirming the previously reported beneficial effect of ACh signaling on bone mass accrual. Increasing brain ACh levels through the use of the blood brain barrier (BBB)-permeable acetylcholinesterase inhibitor (AChEI) galantamine increased trabecular bone mass in adult female mice, whereas a peripheral increase in ACh levels induced by the BBB-impermeable AChEI pyridostigmine caused trabecular bone loss. AChEIs did not alter skeletal norepinephrine level, and induced an overall increase in osteoblast and osteoclast densities, two findings that do not support a reduction in sympathetic outflow as the mechanism involved in the pro-anabolic effect of galantamine on the skeleton. In addition, we did not detect changes in the commitment of skeletal progenitor cells to the osteoblast lineage in vivo in AChEI-treated mice, nor a direct impact of these drugs in vitro on the survival and differentiation of osteoblast and osteoclast progenitors. Last, ChT heterozygosity and galantamine treatment triggered bone changes in female mice only, thus revealing the existence of a gender-specific skeletal response to brain ACh level. In conclusion, this study supports the stimulatory effect of central ACh on bone mass accrual, shows that it also promotes peak bone mass maintenance in adult mice, and suggests that central ACh regulates bone mass via different mechanisms in growing versus sexually mature mice. © 2020 American Society for Bone and Mineral Research.

Therapeutic Effects of Tryptanthrin and Tryptanthrin-6-Oxime in Models of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic autoimmune disease involving joint and bone damage that is mediated in part by proteases and cytokines produced by synovial macrophages and fibroblast-like synoviocytes (FLS). Although current biological therapeutic strategies for RA have been effective in many cases, new classes of therapeutics are needed. We investigated anti-inflammatory properties of the natural alkaloid tryptanthrin (TRYP) and its synthetic derivative tryptanthrin-6-oxime (TRYP-Ox). Both TRYP and TRYP-Ox inhibited matrix metalloproteinase (MMP)-3 gene expression in interleukin (IL)-1β-stimulated primary human FLS, as well as IL-1β–induced secretion of MMP-1/3 by FLS and synovial SW982 cells and IL-6 by FLS, SW982 cells, human umbilical vein endothelial cells (HUVECs), and monocytic THP-1 cells, although TRYP-Ox was generally more effective and had no cytotoxicity in vitro. Evaluation of the therapeutic potential of TRYP and TRYP-Ox in vivo in murine arthritis models showed that both compounds significantly attenuated the development of collagen-induced arthritis (CIA) and collagen-antibody–induced arthritis (CAIA), with comparable efficacy. Collagen II (CII)-specific antibody levels were similarly reduced in TRYP- and TRYP-Ox-treated CIA mice. TRYP and TRYP-Ox also suppressed proinflammatory cytokine production by lymph node cells from CIA mice, with TRYP-Ox being more effective in inhibiting IL-17A, granulocyte-macrophage colony-stimulating factor (GM-CSF), and receptor activator of nuclear factor-κB ligand (RANKL). Thus, even though TRYP-Ox generally had a better in vitro profile, possibly due to its ability to inhibit c-Jun N-terminal kinase (JNK), both TRYP and TRYP-Ox were equally effective in inhibiting the clinical symptoms and damage associated with RA. Overall, TRYP and/or TRYP-Ox may represent potential new directions for the pursuit of novel treatments for RA.

The Unraveling: Cardiac and Musculoskeletal Defects and Their Role in Common Alzheimer Disease Morbidity and Mortality

Alzheimer disease (AD) is characterized by deterioration of cognitive capabilities with an estimated 44 million individuals worldwide living with it. Beyond memory deficits, the most common AD co-morbidities include swallowing defects (muscle), fractures (bone, muscle), and heart failure. The underlying causes of these co-morbidities and their role in AD pathophysiology are currently unknown. This review is the first to summarize the emerging picture of the cardiac and musculoskeletal deficits in human AD. We present the involvement of the heart, characterized by diastolic heart failure, the presence of amyloid deposits, and electrophysiological changes, compared with age-matched control subjects. The characteristic musculoskeletal defects in AD come from recent clinical studies and include potential underlying mechanisms (bone) in animal models. These studies detail a primary muscle weakness (without a loss of muscle mass) in patients with mild cognitive impairment, with progression of cognitive impairment to AD associating with ongoing muscle weakness and the onset of muscle atrophy. We conclude by reviewing the loss of bone density in patients with AD, paralleling the increase in fracture and fall risk in specific populations. These studies paint AD as a systemic disease in broad strokes, which may help elucidate AD pathophysiology and to allow for new ways of thinking about therapeutic interventions, diagnostic biomarkers, and the pathogenesis of this multidisciplinary disease.

Acetylcholinesterase Inhibitors Are Associated with Reduced Fracture Risk among Older Veterans with Dementia

Acetylcholinesterase inhibitors (AChEIs) have been noted to increase bone density and quality in mice. Human studies are limited but suggest an association with improved bone healing after hip fracture. We examined the relationship between AChEI use and fracture risk in a national cohort of 360,015 male veterans aged 65 to 99 years with dementia but without prior fracture using Veterans Affairs (VA) hospital, Medicare, and pharmacy records from 2000 to 2010. Diagnosis of dementia, any clinical fracture (excluding facial and digital), comorbidities, and medications were identified using ICD-9 and drug class codes. Cox proportional hazard models considering AChEI use as a time-varying covariate and adjusting for fall and fracture risk factors compared the time-to-fracture in AChEI users versus non-AChEI users. Potential confounders included demographics (age, race, body mass index), comorbidities associated with fracture or falls (diabetes, lung disease, stroke, Parkinson's, seizures, etc.) and medications associated with fracture or falls (bisphosphonates, glucocorticoids, androgen deprivation therapy [ADT], proton pump inhibitors [PPIs], selective serotonin receptor inhibitors [SSRIs], etc.). Competing mortality risk was considered using the methods of Fine and Gray. To account for persistent effects on bone density or quality that might confer protection after stopping the medication, we completed a secondary analysis using the medication possession ratio (MPR) as a continuous variable in logistic regression models and also compared MPR increments of 10% to minimal/no use (MPR 0 to <0.10). Among older veterans with diagnosis of dementia, 20.1% suffered a fracture over an average of 4.6 years of follow-up. Overall, 42.3% of the cohort were prescribed AChEIs during the study period. The hazard of any fracture among AChEI users compared with those on other/no dementia medications was significantly lower in fully adjusted models (hazard ratio [HR] = 0.81; 95% confidence interval [CI] 0.75-0.88). After considering competing mortality risk, fracture risk remained 18% lower in veterans using AChEIs (HR = 0.82; 95% CI 0.76-0.89). © 2019 American Society for Bone and Mineral Research. Published 2019. This article is a U.S. Government work and is in the public domain in the USA.

A road map for understanding molecular and genetic determinants of osteoporosis

Osteoporosis is a highly prevalent disorder characterized by low bone mineral density and an increased risk of fracture, termed osteoporotic fracture. Notably, bone mineral density, osteoporosis and osteoporotic fracture are highly heritable; however, determining the genetic architecture, and especially the underlying genomic and molecular mechanisms, of osteoporosis in vivo in humans is still challenging. In addition to susceptibility loci identified in genome-wide association studies, advances in various omics technologies, including genomics, transcriptomics, epigenomics, proteomics and metabolomics, have all been applied to dissect the pathogenesis of osteoporosis. However, each technology individually cannot capture the entire view of the disease pathology and thus fails to comprehensively identify the underlying pathological molecular mechanisms, especially the regulatory and signalling mechanisms. A change to the status quo calls for integrative multi-omics and inter-omics analyses with approaches in 'systems genetics and genomics'. In this Review, we highlight findings from genome-wide association studies and studies using various omics technologies individually to identify mechanisms of osteoporosis. Furthermore, we summarize current studies of data integration to understand, diagnose and inform the treatment of osteoporosis. The integration of multiple technologies will provide a road map to illuminate the complex pathogenesis of osteoporosis, especially from molecular functional aspects, in vivo in humans.

Association Between Acetylcholinesterase Inhibitors and Osteoporotic Fractures in Older Persons With Alzheimer's Disease

OBJECTIVE

To identify the association between the use of acetylcholinesterase inhibitors (AChEIs) and risk of osteoporotic fractures in older persons with Alzheimer's disease (AD).

DESIGN, SETTING, AND PARTICIPANTS

A nested case-control study was conducted using the Korean National Health Insurance Service-National Elderly Cohort database. Patients with AD who were newly diagnosed with osteoporotic fractures were identified as cases. Up to 3 controls were matched with cases according to age, sex, and duration of follow-up.

METHODS

Participants were considered as exposed to AChEIs if they had been prescribed at least 1 AChEI during a period of 2 years before the index date. A conditional logistic regression was performed to estimate the adjusted odds ratios with 95% confidence intervals for the association between the use of AChEIs and osteoporotic fractures in patients with AD. We also examined the impact of dose, duration of treatment, and timing of exposure on the estimates of the association between the use of AChEIs and risk of osteoporotic fractures.

RESULTS

The study cohort comprised 45,006 patients diagnosed with AD, of which 9470 patients, including 2385 cases and 7085 controls, were available for the study. The mean ages (standard deviations) were 78.6 (6.9) years in the cases and 80.0 (6.9) years in the controls. Adjusted odds ratios for the association between the use of AChEIs and osteoporotic fractures in patients with AD was 1.18 (95% confidence interval 1.07-1.31).

CONCLUSIONS AND IMPLICATIONS

Our data indicated that the use of AChEIs was not associated with a reduced risk of osteoporotic fractures in patients with AD; in contrast, their use was associated with a mild increased risk of osteoporotic fractures. Thus, clinicians should consider the possibility of AChEIs-associated fractures among older persons with AD. Findings of this study will support shared decision making among prescribers, patients, and caregivers.

Alzheimer Dementia in the Orthopaedic Patient

Alzheimer disease is a neurologic disorder characterized by the progressive cognitive decline. As the population continues to age, orthopaedic surgeons need to become familiar with surgical and nonsurgical treatment considerations in this complex population. Despite the advances in geriatric and dementia care, surgical and postoperative management of both elective and emergent surgery remain complex and controversial in this patient population. Appropriate perioperative and postoperative management can optimize outcomes, and the management can significantly affect the quality of life of patient and caregiver and limit disease burden. Any treatment decision should be guided first and foremost by the goals of care as agreed between the surgeon, other providers, and family. Surgical management must be demand matched to the patient accounting for the severity of disease, life expectancy, and the social support system. The authors conducted a literature review of Alzheimer dementia care in orthopaedic patients via a Pubmed search of relevant articles published since 1980.

Application of donepezil increased collagen 1 expression in mesenchymal stroma cells of an ovine osteoporosis model

OBJECTIVES

Donepezil inhibits the acetylcholine degradation molecule acetylcholinesterase (AChE). Clinical studies reported that Alzheimer's disease (AD) patients with hip fractures had improved bone quality and better fracture healing if they were treated with AD medication donepezil. We asked whether mesenchymal stroma cells (MSC) from an osteoporosis sheep model treated with donepezil increased their proliferation rate and mRNA expression.

METHODS

Sheep were divided into 4 groups: a) untreated control group, b) sheep with bilateral ovariectomy (OVX), c) sheep with OVX and malnutrition, and d) sheep with OVX, malnutrition, and application of corticosteroid. After 8 months MSC were isolated of iliac crest biopsy, treated with donepezil, and AChE activity, proliferation rate, and mRNA expression were analyzed.

RESULTS

Application of donepezil resulted in a significant decrease of AChE activity. Inhibition of AChE did not lead to a significant increase in proliferation. Expression of the osteogenic marker osteocalcin was not regulated by donepezil while the mRNA concentration of collagen was increased.

CONCLUSION

AChE inhibition via donepezil resulted in an increased synthesis of osteoid which consists mainly of collagen. Thus, we suppose that increased acetylcholine levels through AChE inhibition do not support MSC proliferation but osteogenic activity probably combined with osteogenic differentiation.

Contribution of Inhibitor of Differentiation and Estrogenic Endocrine Disruptors to Neurocognitive Disorders

The devastating growth in the worldwide frequency of neurocognitive disorders and its allied difficulties, such as decline in memory, spatial competency, and ability to focus, poses a significant psychological public health problem. Inhibitor of differentiation (ID) proteins are members of a family of helix-loop-helix (HLH) transcription factors. ID proteins have been demonstrated to be involved in neurodevelopmental and depressive diseases and, thus, may influence neurocognitive deficiencies due to environmental exposure. Previously, it has been demonstrated that environmental factors, such as estrogenic endocrine disruptors (EEDs), have played an essential role in the influence of various neurocognitive disorders such as Alzheimer’s, dementia, and Parkinson’s disease. Based on this increasing number of reports, we consider the impact of these environmental pollutants on ID proteins. Better understanding of how these ID proteins by which EED exposure can affect neurocognitive disorders in populations will prospectively deliver valuable information in the impediment and regulation of these diseases linked with environmental factor exposure.