Bazedoxifene improves renal function and increases renal phosphate excretion in patients with postmenopausal osteoporosis

Strong protection by bazedoxifene against chemically-induced ferroptotic neuronal death in vitro and in vivo

Ferroptosis, a form of regulated cell death associated with glutathione depletion and excess lipid peroxidation, can be induced in cultured cells by chemicals (e.g., erastin and RSL3). It has been shown that protein disulfide isomerase (PDI) is a mediator of chemically-induced ferroptosis and also a crucial target for ferroptosis protection. The present study reports that bazedoxifene (BAZ), a selective estrogen receptor modulator, is an inhibitor of PDI and can strongly rescue neuronal cells from chemically-induced oxidative ferroptosis. We find that BAZ can directly bind to PDI and inhibit its catalytic activity. Computational modeling analysis reveals that BAZ forms a hydrogen bond with PDI's His256 residue. Inhibition of PDI by BAZ markedly reduces iNOS and nNOS dimerization (i.e., catalytic activation) and NO accumulation, and these effects of BAZ are associated with reductions in cellular ROS and lipid-ROS and protection against chemically-induced ferroptosis. In addition, the direct antioxidant activity of BAZ may also partially contribute to its protection against chemically-induced ferroptosis. In vivo animal experiments show that mice treated with BAZ are strongly protected against kainic acid-induced oxidative hippocampal neuronal injury and memory deficits. Together, these results reveal that BAZ is a potent inhibitor of PDI and can strongly protect against chemically-induced ferroptosis in hippocampal neurons both in vitro and in vivo. This work provides evidence for an estrogen receptor-independent, PDI-mediated novel mechanism of neuroprotection by BAZ.

A comprehensive review and advanced biomolecule-based therapies for osteoporosis

BACKGROUND

The prevalence of osteoporosis (OP) on a global scale is significantly elevated that causes life threatening issues. The potential of groundbreaking biomolecular therapeutics in the field of OP is highly encouraging. The administration of biomolecular agents has the potential to mitigate the process of bone demineralization while concurrently augmenting the regenerative capacity of bone tissue, thereby facilitating a personalized therapeutic approach. Biomolecules-based therapies showed promising results in term of bone mass protection and restoration in OP.

AIM OF REVIEW

We summarized the recent biomolecular therapies with notable progress in clinical, demonstrating the potential to transform illness management. These treatments frequently utilize different biomolecule based strategies. Biomolecular therapeutics has a targeted character, which results in heightened specificity and less off-target effects, ultimately leading to increased patient outcomes. These aspects have the capacity to greatly enhance the management of OP, thus resulting in a major enhancement in the quality of life encountered by individuals affected by this condition.

Chronic kidney disease and menopausal health: An EMAS clinical guide

Kidney diseases are related to the aging process. Ovarian senescence and the loss of estrogen's renoprotective effects are directly associated with a decline in renal function and indirectly with an accumulation of cardiometabolic risk factors. The latter can predispose to the development of chronic kidney disease (CKD). Conversely, CKD diagnosed during reproductive life adversely affects ovarian function.

AIM

To set out an individualized approach to menopause management in women with CKD.

MATERIALS AND METHODS

Literature review and consensus of expert opinion.

SUMMARY RECOMMENDATIONS

Menopause hormone therapy can be given to women with CKD. The regimen should be selected on the basis of patient preference and the individual's cardiovascular risk. The dose of hormonal and non-hormonal preparations should be adjusted in accordance with the patient's creatinine clearance. The management of a postmenopausal woman with CKD should focus on lifestyle advice as well as regular monitoring of the main cardiovascular risk factors and evaluation of bone mineral density. Tailored multidisciplinary advice should be given to women with comorbidities such as diabetes, dyslipidemia, and hypertension. Management of osteoporosis should be based on the severity of the CKD.

Height loss is associated with decreased kidney function: The Japan Specific Health Checkups (J-SHC) Study

AIM

Height loss that occurs with aging is a common phenomenon associated with musculoskeletal abnormalities, such as osteoporosis and sarcopenia. Notably, such height loss is also associated with poor outcomes, including cardiovascular disease and mortality. In this study, we investigated the relationship between height loss and kidney outcome.

METHODS

This longitudinal study includes data from the Japan Specific Health Checkups Study from 2008 to 2014. Height loss was estimated using the first three visits (visits 1-3), and kidney outcomes were evaluated using data from the following visits (visit 3 to the last visit). The annual height change for each participant was estimated using mixed-effects model, and participants were divided into five groups according to the quintile of the rate. The association between height change and the incidence of 1.5-fold increase in serum creatinine level from baseline was analyzed using Cox regression analysis. The decline rates of estimated glomerular filtration rate among the groups were compared using a mixed-effects model.

RESULTS

In total, 187 682 participants were included in the analyses. The median rate of height change was -0.11 cm/year. The adjusted hazard ratio (95% confidence interval) for 1.5-fold increase in serum creatinine level in participants with the steepest category of height decline (Q1; Quintile 1) was 1.45 (1.26-1.67) compared with the reference (Q4; Quintile 4). The decline of the estimated glomerular filtration rate in Q1 (-1.25 mL/min/1.73 m² /year) was significantly higher than that of the reference: Q4 (-0.92 mL/min/1.73 m² /year) (P for interaction <0.001).

CONCLUSION

Height loss is associated with a rapid decline in kidney function. Geriatr Gerontol Int 2023; ••: ••-••.

Mechanism of Erzhiwan in treating osteoporosis based on molecular docking technology and molecular dynamics simulation

This experiment was a network pharmacology research based on the theoretical system of traditional Chinese medicine. TCMSP database, PubChem database, RCSB database, and SwissTargetPrediction database were used to study the effective chemical constituents of Ligustri lucidi Fructus and Ecliptae Herba in Erzhiwan, a traditional prescription for nourishing the liver and kidney. Then Genecards database, OMIM database, OMIM Gene Map, and Metascape database were used to study the therapeutic targets of osteoporosis. At last, Cytoscape 3.6.0 software, its built-in Bisogenet and CytoNCA, AutoDockTools-1.5.6 software, PYMOL-2.2.0 software, and Gromacs software, by drawing the relationship diagram between chemical components and disease targets, PPI network of disease, semi-flexible molecular docking technology, evaluation and analysis of enrichment pathway, and molecular dynamics simulation, were used to study the therapeutic mechanism of Erzhiwan on osteoporosis. It is found that the intervention and regulation of Erzhiwan on osteoporosis were mainly realized through multiple targets of active ingredients and multiple pathways, which provided support for the continued development of Erzhiwan.

Enhanced osteogenic differentiation of alendronate-conjugated nanodiamonds for potential osteoporosis treatment

Background

Alendronate (Alen) is promising material used for bone-targeted drug delivery due to its high bone affinity and therapeutic effects on bone diseases. In addition, Alen can enhance the osteogenic differentiation of osteoblastic cell. Recently, nanodiamonds (NDs) with hardness, non-toxicity, and excellent biocompatibility are employed as promising materials for carrier systems and osteogenic differentiation. Therefore, we prepared Alen-conjugated NDs (Alen-NDs) and evaluated their osteogenic differentiation performances.

Methods

Alen-NDs were synthesized using DMTMM as a coupling reagent. Morphological change of Mouse calvaria-derived preosteoblast (MC3T3-E1) treated with Alen-NDs was observed using the confocal microscope. The osteogenic differentiation was confirmed by cell proliferation, alkaline phosphatase (ALP), calcium deposition, and real-time polymerase chain reaction assay.

Results

Alen-NDs were prepared to evaluate their effect on the proliferation and differentiation of osteoblastic MC3T3-E1 cells. The Alen-NDs had a size of about 100 nm, and no cytotoxicity at less than 100 μg/mL of concentration. The treatment of NDs and Alen-NDs reduced the proliferation rate of MC3T3-E1 cells without cell death. Confocal microscopy images confirmed that the treatment of NDs and Alen-NDs changed the cellular morphology from a fibroblastic shape to a cuboidal shape. Flow cytometry, alkaline phosphatase (ALP) activity, calcium deposition, and real-time polymerase chain reaction (RT-PCR) confirmed the higher differentiation of MC3T3-E1 cells treated by Alen-NDs, compared to the groups treated by osteogenic medium and NDs. The higher concentration of Alen-ND treated in MC3T3-E1 resulted in a higher differentiation level.

Conclusions

Alen-NDs can be used as potential therapeutic agents for osteoporosis treatment by inducing osteogenic differentiation.

Bone Quality in Chronic Kidney Disease Patients: Current Concepts and Future Directions - Part II

Background

Patients with chronic kidney disease (CKD) have an increased risk of osteoporotic fractures, which is due not only to low bone volume and mass but also poor microarchitecture and tissue quality. The pharmacological and nonpharmacological interventions detailed, herein, are potential approaches to improve bone health in CKD patients. Various medications build up bone mass but also affect bone tissue quality. Antiresorptive therapies strikingly reduce bone turnover; however, they can impair bone mineralization and negatively affect the ability to repair bone microdamage and cause an increase in bone brittleness. On the other hand, some osteoporosis therapies may cause a redistribution of bone structure that may improve bone strength without noticeable effect on BMD. This may explain why some drugs can affect fracture risk disproportionately to changes in BMD.

Summary

An accurate detection of the underlying bone abnormalities in CKD patients, including bone quantity and quality abnormalities, helps in institution of appropriate management strategies. Here in this part II, we are focusing on advancements in bone therapeutics that are anticipated to improve bone health and decrease mortality in CKD patients.

Key Messages

Therapeutic interventions to improve bone health can potentially advance life span. Emphasis should be given to the impact of various therapeutic interventions on bone quality.

Importance of Considering Malnutrition and Sarcopenia in Order to Improve the QOL of Elderly Hemodialysis Patients in Japan in the Era of 100-Year Life

In the current aging society of Japan, malnutrition and resultant sarcopenia have been widely identified as important symptomatic indicators of ill health and can cause impairments of longevity and quality of life in older individuals. Elderly individuals are recommended to have sufficient calorie and protein intake so as to enjoy a satisfactory quality of life, including maintaining activities of daily living in order to avoid emaciation and sarcopenia. The prevalence of emaciation and sarcopenia in elderly hemodialysis (HD) patients in Japan is higher than in non-HD elderly subjects due to the presence of malnutrition and sarcopenia associated with chronic kidney disease (CKD). Furthermore, comorbidities, such as diabetes and osteoporosis, induce malnutrition and sarcopenia in HD patients. This review presents findings regarding the mechanisms of the development of these early symptomatic conditions and their significance for impaired QOL and increased mortality in elderly HD patients.

Estrogen and estrogen receptors in kidney diseases

Acute kidney injury (AKI) and chronic kidney disease (CKD) are posing great threats to global health within this century. Studies have suggested that estrogen and estrogen receptors (ERs) play important roles in many physiological processes in the kidney. For instance, they are crucial in maintaining mitochondrial homeostasis and modulating endothelin-1 (ET-1) system in the kidney. Estrogen takes part in the kidney repair and regeneration via its receptors. Estrogen also participates in the regulation of phosphorus homeostasis via its receptors in the proximal tubule. The ERα polymorphisms have been associated with the susceptibilities and outcomes of several renal diseases. As a consequence, the altered or dysregulated estrogen/ERs signaling pathways may contribute to a variety of kidney diseases, including various causes-induced AKI, diabetic kidney disease (DKD), lupus nephritis (LN), IgA nephropathy (IgAN), CKD complications, etc. Experimental and clinical studies have shown that targeting estrogen/ERs signaling pathways might have protective effects against certain renal disorders. However, many unsolved problems still exist in knowledge regarding the roles of estrogen and ERs in distinct kidney diseases. Further research is needed to shed light on this area and to enable the discovery of pathway-specific therapies for kidney diseases.

Effects of burosumab on osteocalcin and bone mineral density in patient with 15-year history of nonremission tumor-induced osteomalacia initially treated with conventional therapy: Case report

Excess fibroblast growth factor 23 (FGF23) causes hypophosphatemic osteomalacia, which is associated with impaired bone matrix mineralization. Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome caused by over-secretion of FGF23 from a tumor. Burosumab, a fully human monoclonal antibody with activities against FGF23, was initially approved in Japan before the rest of the world for treatment of FGF23-associated hypophosphatemic osteomalacia by TIO. We report here a patient with a 15-year history of non-remission TIO initially treated with conventional therapy who was then switched to burosumab treatment. Persistent hypophosphatemia and a relative low level of osteocalcin (bone Gla protein, BGP) compared with bone alkaline phosphatase (BAP) level, indicating poor matrix mineralization, developed during long-term conventional therapy. Repeated surgical and stereotactic body radiation treatments did not result in complete resection of the causable tumor, and bone mineral density (BMD) gradually decreased. Ultimately, burosumab treatment was administered and the serum Pi concentration immediately normalized, while both BGP and BMD also showed a good response. This is first known case report of the detailed efficacy of burosumab for nonremission TIO as an alternative to conventional therapy.