Long-term effects of denosumab on bone mineral density and turnover markers in patients undergoing hemodialysis.

INTRODUCTION: Denosumab, a fully human anti-RANKL monoclonal antibody, is a widely used osteoporosis treatment that is increasingly being used in patients undergoing dialysis; however, its long-term efficacy and safety in these patients remain unknown. MATERIALS AND METHODS: This observational study comprised individuals aged ≥ 20 years undergoing hemodialysis and receiving denosumab. After denosumab administration, we analyzed the long-term changes in bone mineral density (BMD) and levels of bone turnover markers (BTMs) and calcium. RESULTS: The study included 45 patients who have been receiving denosumab for a median duration of 3.8 (interquartile range, 2.5-6.7) years. Tartrate-resistant acid phosphatase 5b (TRACP-5b) levels decreased from a median of 595 (434-778) mU/dL at baseline to 200 (141-430) mU/dL after 6 months of denosumab administration (P < 0.001) and remained low thereafter. Similarly, bone-specific alkaline phosphatase (BAP) levels decreased from a median of 18.2 (15.9-25.8) µg/L at baseline to 12.4 (9.9-15.6) µg/L after 6 months (P < 0.001) and remained low thereafter. Meanwhile, BMD, as assessed with dual energy X-ray absorptiometry and measured at the distal 1/3 of the radius, did not decrease (0.465 ± 0.112 g/cm2 at baseline vs. 0.464 ± 0.112 g/cm2 after administration; P = 0.616). Regarding hypocalcemia, corrected calcium levels reached were the lowest at 7 days after administration and normalized within 30 days. CONCLUSION: The study showed long-term suppression of TRACP-5b and BAP levels and sustaining BMD after denosumab administration over an extended period in patients undergoing hemodialysis.

The Role of Rosavin in the Pathophysiology of Bone Metabolism.

Rosavin, a phenylpropanoid in Rhodiola rosea's rhizome, and an adaptogen, is known for enhancing the body's response to environmental stress. It significantly affects cellular metabolism in health and many diseases, particularly influencing bone tissue metabolism. In vitro, rosavin inhibits osteoclastogenesis, disrupts F-actin ring formation, and reduces the expression of osteoclastogenesis-related genes such as cathepsin K, calcitonin receptor (CTR), tumor necrosis factor receptor-associated factor 6 (TRAF6), tartrate-resistant acid phosphatase (TRAP), and matrix metallopeptidase 9 (MMP-9). It also impedes the nuclear factor of activated T-cell cytoplasmic 1 (NFATc1), c-Fos, the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and mitogen-activated protein kinase (MAPK) signaling pathways and blocks phosphorylation processes crucial for bone resorption. Moreover, rosavin promotes osteogenesis and osteoblast differentiation and increases mouse runt-related transcription factor 2 (Runx2) and osteocalcin (OCN) expression. In vivo studies show its effectiveness in enhancing bone mineral density (BMD) in postmenopausal osteoporosis (PMOP) mice, restraining osteoclast maturation, and increasing the active osteoblast percentage in bone tissue. It modulates mRNA expressions by increasing eukaryotic translation elongation factor 2 (EEF2) and decreasing histone deacetylase 1 (HDAC1), thereby activating osteoprotective epigenetic mechanisms, and alters many serum markers, including decreasing cross-linked C-telopeptide of type I collagen (CTX-1), tartrate-resistant acid phosphatase 5b (TRACP5b), receptor activator for nuclear factor κ B ligand (RANKL), macrophage-colony-stimulating factor (M-CSF), and TRAP, while increasing alkaline phosphatase (ALP) and OCN. Additionally, when combined with zinc and probiotics, it reduces pro-osteoporotic matrix metallopeptidase 3 (MMP-3), interleukin 6 (IL-6), and tumor necrosis factor α (TNF-α), and enhances anti-osteoporotic interleukin 10 (IL-10) and tissue inhibitor of metalloproteinase 3 (TIMP3) expressions. This paper aims to systematically review rosavin's impact on bone tissue metabolism, exploring its potential in osteoporosis prevention and treatment, and suggesting future research directions.

Possible roles of short-chain fatty acids produced by oral bacteria in the development of alveolar osteitis.

PURPOSE: Alveolar osteitis (dry sockets) is a painful condition characterized by a limited immune response. It is typically caused by the removal of blood clots from extracted tooth sockets, which leads to the fermentation of trapped food remnants by oral bacteria in the cavities, producing high concentrations of short-chain fatty acids (SCFAs). This study examined the effects of SCFAs on immunity and bone metabolism. METHODS: Mouse macrophage Raw264.7 cells were treated with oral bacteria supernatants or SCFA mixtures, and inducible nitric oxide synthase (iNOS) levels were determined by western blot. The same cells were treated with SCFA mixtures in the presence of receptor activator of nuclear factor-kappa B ligand (RANKL), and osteoclast-like cells were counted. MC3T3-E1 cells were treated with SCFA mixtures and stained with alizarin red S. RESULTS: Raw264.7 cells treated with oral bacterial culture supernatants of Porphyromonas gingivalis and Fusobacterium nucleatum inhibited lipopolysaccharide (LPS)-induced iNOS production, likely due to SCFA content. SCFA mixtures mimicking these supernatants inhibited the number of RANKL-induced tartrate-resistant acid phosphatase (TRAP)-positive cells and MC3T3-E1 cell mineralization. CONCLUSION: These data suggest that SCFAs produced by P. gingivalis and F. nucleatum may reduce the inflammatory response and mildly induce mineralization of the alveolar walls. These results may contribute to the understanding of alveolar osteitis.

Studies on the in vitro mechanism and in vivo therapeutic effect of the antimicrobial peptide ACP5 against Trichophyton mentagrophytes.

Trichophyton mentagrophytes is a zoophilic dermatophyte that can cause dermatophytosis in humans and animals. Antimicrobial peptides (AMPs) are considered as a promising agent to overcome the drug-resistance of T. mentagrophytes. Our findings suggest that cationic antimicrobial peptide (ACP5) not only possesses stronger activity against T. mentagrophytes than fluconazole, but also shows lower toxicity to L929 mouse fibroblast cells than terbinafine. Notably, its resistance development rate after resistance induction was lower than terbinafine. The present study aimed to evaluate the fungicidal mechanism of ACP5 in vitro and its potential to treat dermatophyte infections in vivo. ACP5 at 1 ×MIC completely inhibited T. mentagrophytes spore germination in vitro. ACP5 severely disrupts the mycelial morphology, leading to mycelial rupture. Mechanistically, ACP5 induces excessive ROS production, damaging the integrity of the cell membrane and decreasing the mitochondrial membrane potential, causing irreversible damage in T. mentagrophytes. Furthermore, 1% ACP5 showed similar efficacy to the commercially available drug 1% terbinafine in a guinea pig dermatophytosis model, and the complete eradication of T. mentagrophytes from the skin by ACP5 was verified by tissue section observation. These results indicate that ACP5 is a promising candidate for the development of new agent to combat dermatophyte resistance.

Espondiloencondrodisplasia con desregulación inmune relacionada a ACP5. Reporte de cuatro casos / Spondyloenchondrodysplasia with immune dysregulation related to ACP5. A report of 4 cases

La espondiloencondrodisplasia con desregulación inmune relacionada a ACP5 (SPENCDI #607944, por la sigla de spondyloenchondrodysplasia with immune dysregulation y el número que le corresponde en OMIM, Online Mendelian Inheritance in Man) es una displasia inmuno-ósea poco frecuente con manifestaciones heterogéneas y gravedad variable. Presenta lesiones espondilometafisarias, disfunción inmune y compromiso neurológico. Se reportan aspectos clínicos, radiológicos y genéticos de cuatro niñas con SPENCDI en un hospital pediátrico. Todas presentaron manifestaciones esqueléticas y tres de ellas enfermedad inmunológica grave. Se encontró en tres pacientes la variante probablemente patogénica c.791T>A; p.Met264Lys en homocigosis, y en una paciente las variantes c.791T>A; p.Met264Lys y c.632T>C; p.lle211Thr (variante de significado incierto con predicción patogénica según algoritmos bioinformáticos) en heterocigosis compuesta en ACP5. La presencia de la variante repetida c.791T>A sugiere la posibilidad de un ancestro en común en nuestra población. El reconocimiento y diagnóstico de esta entidad es importante para lograr un oportuno abordaje, que deberá ser multidisciplinario, orientado hacia la prevención de posibles complicaciones.

Spondyloenchondrodysplasia with immune dysregulation related to ACP5 (SPENCDI, OMIM number 607944) is an uncommon immune-skeletal dysplasia with heterogeneous manifestations and variable severity. It is characterized by spondylar and metaphyseal lesions, immune dysfunction, and neurological involvement. Here we report the clinical, radiological and genetic aspects of 4 girls with SPENCDI treated at a children's hospital. They all had skeletal manifestations and 3 developed severe immune disease. In 3 patients, the likely pathogenic variant c.791T>A; p.Met264Lys (homozygous mutation) was observed, while 1 patient had variants c.791T>A; p.Met264Lys and c.632T>C; p.lle211Thr (variant of uncertain significance with pathogenic prediction based on bioinformatics algorithms) caused by a compound heterozygous mutation in ACP5. The repeated presence of variant c.791T>A suggests the possibility of a common ancestor in our population. The recognition and diagnosis of this disorder is important to achieve a timely approach, which should be multidisciplinary and aimed at preventing possible complications.

Morinda officinalis polysaccharide promotes the osteogenic differentiation of human bone marrow-derived mesenchymal stem cells via microRNA-210-3p/scavenger receptor class A member 3.

Morinda officinalis polysaccharide (MOP) is the bioactive ingredient extracted from the root of Morinda officinalis, and Morinda officinalis is applied to treat osteoporosis (OP). The purpose of this study was to determine the role of MOP on human bone marrow mesenchymal stem cells (hBMSCs) and the underlying mechanism. HBMSCs were isolated from bone marrow samples of patients with OP and treated with MOP. Quantitative real-time polymerase chain reaction was adopted to quantify the expression of microRNA-210-3p (miR-210-3p) and scavenger receptor class A member 3 (SCARA3) mRNA. Cell Counting Kit-8 assay was employed to detect cell viability; Terminal-deoxynucleotidyl Transferase Mediated Nick End Labeling assay and flow cytometry were adopted to detect apoptosis; Alkaline Phosphatase (ALP) activity assay kit was applied to detect ALP activity; Western blot was executed to quantify the expression levels of SCARA3, osteogenic and adipogenic differentiation markers. Ovariectomized rats were treated with MOP. Bone mineral density (BMD), serum tartrate-resistant acid phosphatase 5b (TRACP 5b), and N-telopeptide of type I collagen (NTx) levels were assessed by BMD detector and Enzyme-linked immunosorbent assay kits. It was revealed that MOP could promote hBMSCs' viability and osteogenic differentiation and inhibit apoptosis and adipogenic differentiation. MOP could also upregulate SCARA3 expression through repressing miR-210-3p expression. Treatment with MOP increased the BMD and decreased the TRACP 5b and NTx levels in ovariectomized rats. MOP may boost the osteogenic differentiation and inhibit adipogenic differentiation of hBMSCs by miR-210-3p/SCARA3 axis.

Macrophage expressed tartrate-resistant acid phosphatase 5 promotes pulmonary fibrosis progression.

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disorder involving scarring of pulmonary tissue and a subsequent decrease in respiratory capacity, ultimately resulting in death. Tartrate resistant acid phosphatase 5 (ACP5) plays a role in IPF but the exact mechanisms are yet to be elucidated. In this study, we have utilized various perturbations of the bleomycin mouse model of IPF including genetic knockout, RANKL inhibition, and macrophage adoptive transfer to further understand ACP5's role in pulmonary fibrosis. Genetic ablation of Acp5 decreased immune cell recruitment to the lungs and reduced the levels of hydroxyproline (reflecting extracellular matrix-production) as well as histological damage. Additionally, gene expression profiling of murine lung tissue revealed downregulation of genes including Ccl13, Mmp13, and Il-1α that encodes proteins specifically related to immune cell recruitment and macrophage/fibroblast interactions. Furthermore, antibody-based neutralization of RANKL, an important inducer of Acp5 expression, reduced immune cell recruitment but did not decrease fibrotic lung development. Adoptive transfer of Acp5-/- bone marrow-derived monocyte (BMDM) macrophages 7 or 14 days after bleomycin administration resulted in reductions of cytokine production and decreased levels of lung damage, compared to adoptive transfer of WT control macrophages. Taken together, the data presented in this study suggest that macrophage derived ACP5 plays an important role in development of pulmonary fibrosis and could present a tractable target for therapeutic intervention in IPF.

Spondyloenchondrodysplasia with immune dysregulation related to ACP5. A report of 4 cases. / Espondiloencondrodisplasia con desregulación inmune relacionada a ACP5. Reporte de cuatro casos.

Spondyloenchondrodysplasia with immune dysregulation related to ACP5 (SPENCDI, OMIM number 607944) is an uncommon immune-skeletal dysplasia with heterogeneous manifestations and variable severity. It is characterized by spondylar and metaphyseal lesions, immune dysfunction, and neurological involvement. Here we report the clinical, radiological and genetic aspects of 4 girls with SPENCDI treated at a children's hospital. They all had skeletal manifestations and 3 developed severe immune disease. In 3 patients, the likely pathogenic variant c.791T>A; p.Met264Lys (homozygous mutation) was observed, while 1 patient had variants c.791T>A; p.Met264Lys and c.632T>C; p.lle211Thr (variant of uncertain significance with pathogenic prediction based on bioinformatics algorithms) caused by a compound heterozygous mutation in ACP5. The repeated presence of variant c.791T>A suggests the possibility of a common ancestor in our population. The recognition and diagnosis of this disorder is important to achieve a timely approach, which should be multidisciplinary and aimed at preventing possible complications.

La espondiloencondrodisplasia con desregulación inmune relacionada a ACP5 (SPENCDI #607944, por la sigla de spondyloenchondrodysplasia with immune dysregulation y el número que le corresponde en OMIM, Online Mendelian Inheritance in Man) es una displasia inmuno-ósea poco frecuente con manifestaciones heterogéneas y gravedad variable. Presenta lesiones espondilometafisarias, disfunción inmune y compromiso neurológico. Se reportan aspectos clínicos, radiológicos y genéticos de cuatro niñas con SPENCDI en un hospital pediátrico. Todas presentaron manifestaciones esqueléticas y tres de ellas enfermedad inmunológica grave. Se encontró en tres pacientes la variante probablemente patogénica c.791T>A; p.Met264Lys en homocigosis, y en una paciente las variantes c.791T>A; p.Met264Lys y c.632T>C; p.lle211Thr (variante de significado incierto con predicción patogénica según algoritmos bioinformáticos) en heterocigosis compuesta en ACP5. La presencia de la variante repetida c.791T>A sugiere la posibilidad de un ancestro en común en nuestra población. El reconocimiento y diagnóstico de esta entidad es importante para lograr un oportuno abordaje, que deberá ser multidisciplinario, orientado hacia la prevención de posibles complicaciones.

[Mechanism of Qingluo Tongbi Formula for regulating immune-bone erosion in rheumatoid arthritis].

OBJECTIVE: To explore the mechanism of Qingluo Tongbi formula for regulating "immune-bone erosion" in rheumatoid arthritis (RA). METHODS: Sixty-four RA patients were randomized into two groups to receive treatment with oral methotrexate or Qingluo Tongbi Formula for 12 weeks. Flow cytometry was used to analyze the changes in the percentages of CD3-CD19+, CD19+CD27 and CD19+BAFFR+B cell subpopulations in peripheral blood of the patients, and serum levels of B cell activating factor (BAFF), RANKL, RANK and osteoprotegerin (OPG) levels were detected using ELISA. Before and after the treatment, serum levels of ß-CTX, TRACP-5b, BGP, BALP, and PINP were measured with ELISA, and bone mineral density was determined with DXEA dual-energy X-ray absorptiometry. In the cell experiment, RAW264.7 cells were induced to differentiated into osteoclasts and treated with Qingluo Tongbi Formula at low-, moderate and high doses (125, 250 and 500 µg/mL, respectively) or with methotrexate (2 µg/mL) for 48 h, and the changes in the expression levels of RANKL, RANK, OPG and c-Fos were detected using Western blotting. RESULTS: The B cell subgroups in RA patients were correlated with the RANKL/RANK/OPG system. Treatment with Qingluo Tongbi Formula obviously down-regulated the percentages of the B cell subgroups, lowered serum levels of BAFF, ß-CTX and TRACP-5b, increased the levels of BGP, BALP and PINP, and improved lumbar bone density of RA patients (P<0.05); All these changes were significantly correlated with the regulation of B cell expressions (P<0.05). In RAW264.7 cells-derived osteoclasts, Qingluo Tongbi Formula significantly decreased the expressions of RANKL, RANK and c-Fos and increased the expression of OPG (P<0.05). CONCLUSION: Qingluo Tongbi Formula inhibits bone erosion in RA possibly by regulating B cell subset percentages and BAFF expression and inhibiting osteoclast differentiation via the RANKL/RANK/OPG pathway.

Prevalence and clinical outcomes of vitamin D deficiency among Japanese multiple myeloma patients: a single-center observational study.

PURPOSE: Vitamin D plays a crucial role in skeletal metabolism and holds significant importance in the pathophysiology of multiple myeloma (MM). This study aimed to determine the prevalence of vitamin D deficiency among Japanese MM patients and its correlation with clinical outcomes. METHODS: Serum 25-hydroxyvitamin D (25(OH)D) levels were assessed in 68 MM patients at a single institution in Japan, analyzing their association with clinical status, laboratory parameters including procollagen type 1 N-propeptide (P1NP) and tartrate-resistant acid phosphatase 5b (TRACP-5b), health-related quality of life (HR-QOL) scores, and overall survival. Additionally, patients with suboptimal 25(OH)D levels received cholecalciferol supplementation (1000 IU/day), and changes in laboratory parameters were monitored. RESULTS: The median 25(OH)D level was 22 ng/ml, with 32% and 51% of patients exhibiting vitamin D deficiency (< 20 ng/ml) and insufficiency (20-29 ng/ml), respectively. The 25(OH)D levels were unrelated to sex, age, MM stage, or bone lesions, but the vitamin D-deficient group showed a tendency towards lower HR-QOL scores. Among patients achieving complete remission, vitamin D supplementation increased P1NP, while TRACP-5b remained unchanged. Overall survivals from vitamin D measurement and from MM diagnosis were significantly worse in the vitamin D-deficient group compared to the vitamin D-insufficient/-sufficient group. CONCLUSION: The study identified a considerable number of Japanese MM patients with insufficient serum vitamin D levels, with one-third being deficient. Additionally, vitamin D deficiency predicted poor overall survival in Japanese MM patients. Further investigation is required to determine whether vitamin D supplementation can improve the frailty and survival of vitamin D-deficient MM patients.

Number of contiguous vertebral cross-links in the spine indicates bone formation: a cross-sectional study.

BACKGROUND: As an indicator to evaluate the risk of fracture in diffuse idiopathic skeletal hyperostosis, the maximum number of vertebral bodies' bone cross-linked with contiguous adjacent vertebrae (max VB) was developed. This study retrospectively investigates the relationship between max VB, bone mineral density (BMD), and bone metabolic markers (BMM). METHODS: In this cross-sectional study (from April 2010 to January 2022), males (n = 114) with various max VB from the thoracic vertebra to the sacrum, measured using computed tomography scans, were selected to assess femur BMD and BMM. The association of max VB with the total type I procollagen N-terminal propeptide (P1NP), tartrate-resistant acid phosphatase 5b (TRACP-5b), and bone turnover ratio (BTR = TRACP-5b/P1NP) as well as its relationship with femur BMD with P1NP and TRACP-5b, were investigated. Furthermore, the relationship between P1NP and TRACP-5b was investigated. RESULTS: P1NP increased in proportion to max VB and TRACP-5b increased in proportion to P1NP. Moreover, BTR was inversely proportional to max VB. Finally, femur BMD was inversely proportional to P1NP and TRACP-5b. CONCLUSION: As max VB increased with P1NP-a potential osteogenesis indicator-and BTR was inversely proportional to max VB with compensatory TRACP-5b increase, max VB can be considered as a possible predictor of bone fusion.

Interleukin-21 knockout reduces bone loss in ovariectomized mice by inhibiting osteoclastogenesis.

Estrogen deficiency accelerates osteoporosis in elderly women. However, the role of IL-21 in postmenopausal osteoporosis remains unclear. Female wild-type (WT) C57BL/6 and IL-21 knockout (KO) mice were used for ovariectomy (OVX). Here, IL-21 levels were significantly increased in the serum and bone tissues of WT-OVX mice. The trabecular bone space of the femur was significantly increased, and the bone mass was reduced in OVX mice, accompanied by a significant decrease in the maximum load, energy absorption, and elastic modulus indices. In contrast, IL-21 knockout effectively alleviated the effects of OVX on bone mass. Serum TRACP-5b and receptor activator of nuclear factor kappa B ligand (RANKL) levels and osteoclastogenesis were significantly higher in OVX mice than in sham mice, while serum TRACP-5b and RANKL levels and osteoclastogenesis were significantly decreased in IL-21 KO + OVX mice compared to WT + OVX mice. IL-21 knockdown reduces TRACP-5b, RANKL, and osteoclastogenesis, effectively preventing bone resorption and alleviating the progression of OVX-induced osteoporosis.

A Machine Learning-Based Image Segmentation Method to Quantify In Vitro Osteoclast Culture Endpoints.

Quantification of in vitro osteoclast cultures (e.g. cell number) often relies on manual counting methods. These approaches are labour intensive, time consuming and result in substantial inter- and intra-user variability. This study aimed to develop and validate an automated workflow to robustly quantify in vitro osteoclast cultures. Using ilastik, a machine learning-based image analysis software, images of tartrate resistant acid phosphatase-stained mouse osteoclasts cultured on dentine discs were used to train the ilastik-based algorithm. Assessment of algorithm training showed that osteoclast numbers strongly correlated between manual- and automatically quantified values (r = 0.87). Osteoclasts were consistently faithfully segmented by the model when visually compared to the original reflective light images. The ability of this method to detect changes in osteoclast number in response to different treatments was validated using zoledronate, ticagrelor, and co-culture with MCF7 breast cancer cells. Manual and automated counting methods detected a 70% reduction (p < 0.05) in osteoclast number, when cultured with 10 nM zoledronate and a dose-dependent decrease with 1-10 µM ticagrelor (p < 0.05). Co-culture with MCF7 cells increased osteoclast number by ≥ 50% irrespective of quantification method. Overall, an automated image segmentation and analysis workflow, which consistently and sensitively identified in vitro osteoclasts, was developed. Advantages of this workflow are (1) significantly reduction in user variability of endpoint measurements (93%) and analysis time (80%); (2) detection of osteoclasts cultured on different substrates from different species; and (3) easy to use and freely available to use along with tutorial resources.

Equol and Resveratrol Improve Bone Turnover Biomarkers in Postmenopausal Women: A Clinical Trial.

Estrogen deficiency is a major cause of loss of postmenopausal bone mineral density (BMD). This study aimed to evaluate the effects of equol and resveratrol on bone turnover biomarkers in postmenopausal women. Sixty healthy postmenopausal women were randomly assigned to receive 200 mg fermented soy containing 10 mg equol and 25 mg resveratrol or a placebo for 12 months. Whole-body BMD and bone turnover biomarkers, such as deoxypyridinoline (DPD), tartrate-resistant acid phosphatase 5b (TRACP-5b), osteocalcin, and bone-specific alkaline phosphatase (BAP), were measured at baseline and after 12 months of treatment. At the end of treatment, DPD, osteocalcin, and BAP significantly improved in the active group (p < 0.0001 for all) compared to the placebo group. Conversely, TRACP-5b levels were unaffected by supplementation (p = 0.051). Statistically significant changes in the concentrations of DPD (p < 0.0001), osteocalcin (p = 0.0001), and BAP (p < 0.0001) compared to baseline were also identified. Overall, the intervention significantly increased BMD measured in the whole body (p = 0.0220) compared with the placebo. These data indicate that the combination of equol and resveratrol may positively modulate bone turnover biomarkers and BMD, representing a potential approach to prevent age-related bone loss in postmenopausal women.

D-Pinitol Ameliorated Osteoporosis via Elevating D-chiro-Inositol Level in Ovariectomized Mice.

A natural sugar alcohol, D-pinitol, has been reported to be a potential compound for osteoporosis treatment via inhibiting osteoclastgenesis. However, research on the effects of pinitol on osteoporosis in vivo is still limited. The present study investigated the protective effects of pinitol on ovariectomized mice and attempted to elucidate this mechanism in vivo. Four-week-old female ovariectomized ICR mice were employed as a postmenopausal osteoporosis model and treated with pinitol or estradiol (E2) for 7 wk. Thereafter, serum calcium content, phosphorus content, tartrate-resistant acid phosphatase (TRAcP) and bone-specific alkaline phosphatase activity (BALP) were measured. Bilateral femurs were isolated, and bone marrow protein was collected through centrifuge. Dry femurs were weighed, while femur length, cellular bones, and bone mineral content were measured. D-chiro-Inositol (DCI) and myo-inositol (MI) content in serum and bone marrow was measured by GC-MS. At the end of experiment, the serum BALP and TRAcP activities of the OVX mice were suppressed significantly by treatment with either pinitol or E2. Femur weight, cellular bone rate, Ca and P content were improved by pinitol or E2. The DCI content of the serum of OVX decreased significantly, although it recovered to some extent after pinitol treatment. Pinitol significantly increased the ratio of DCI to MI in serum or bone marrow protein in the observed OVX mice. Besides, pinitol had no significant effects on osteoblast viability and differentiation. The present results showed that continuous pinitol intake exerts potent anti-osteoporosis activity via elevating DCI content in serum and bone marrow in OVX mice.

Leptin and melatonin's effects on OVX rodents' bone metabolism.

Purpose: This study aims to examine the effects of leptin and melatonin intervention on bone metabolism in ovariectomize (OVX) rodents, as well as their potential mechanisms of action. Methods: Prepare an OVX model of osteoporosis in rodents and validate the model by collecting bilateral tibia samples for Micro-CT scanning and histological analysis. A control group of normal size, the OVX group, the OVX+Sema4D (Semaphorin 4D) group, the OVX+Sema4D+Leptin group, the OVX+Sema4D+ Melatonin(MT) group and the OVX+Sema4D+Leptin+ MT group were the experimental groups. Adenovirus vector construction and tibial medullary injection validation were conducted in accordance with the aforementioned experimental groups. Four groups of rats were injected with the Sema4D overexpression adenovirus vector into the tibial medullary cavity, and two groups were injected with the Leptin overexpression adenovirus vector. The repair of osteoporosis was observed using micro-CT and histological analysis. Immunohistochemical detection of bone morphogenetic protein-2 (BMP-2) expression in bone tissue was employed to ascertain the amount of osteoclasts in the upper tibial metaphysis, utilizing TRAP(tartrate-resistant acid phosphatase) staining. Results: Increased levels of BV/TV, Tb.N, BMD, and BMC were seen in the OVX+ Sema4D+Leptin, OVX+ Sema4D+MT, and OVX+ Sema4D+Leptin+ MT groups compared to the OVX group, whereas Tb. Sp levels were lowered. When compared to the Sema4D overexpression group, the trabecular bone structure of the OVX + Sema4D + Leptin, OVX + Sema4D + MT, and OVX + Sema4D + Leptin + MT groups is largely intact, tends to be closer, and the amount of trabecular bone increases. The OVX + Sema4D + Leptin + MT group in particular.The expression of BMP-2 was dramatically upregulated (p<0.05), the number of TRAP-stained osteoclasts was significantly reduced (p<0.05), and BALP(bone-derived alkaline phosphatase) and TRAP-5b(tartrate-resistant acid phosphatase-5b) activities were significantly downregulated (p<0.05). Conclusion: In rats with osteoporosis, leptin and melatonin can be seen to augment the trabecular microstructure of the bone, augment bone growth, diminish trabecular harm, and mend the bone. The combined effect is more powerful.

Children with severe acute malnutrition have high rates of bone resorption: A cross-sectional comparative study.

Malnutrition in under-5 children (i.e., children younger than age 5 years) remains a major public health problem. Because of the reductive adaptation in children with severe acute malnutrition (SAM), changes in bone health are often subtle. We hypothesized that children with SAM have higher rates of bone resorption than bone formation, which can be assessed using bone turnover markers. In this cross-sectional comparative study, we evaluated the status of bone turnover markers, serum osteocalcin and serum tartrate-resistant acid phosphatase-5b (TRAP-5b) in under-5 children with SAM. Thirty children (6-59 months) with SAM (defined as per World Health Organization criteria) were enrolled as cases and another 30 children (age and sex matched) with normal nutritional status (weight for height -1 standard deviation [SD] to +1 SD) were enrolled for comparison of bone turnover markers. Serum TRAP-5b concentrations were significantly higher in children with SAM compared with children with normal nutritional status (mean [SD] 22.6 [15.3] vs. 11.3 [9.6], P = .009), whereas serum osteocalcin concentrations were comparable between the 2 groups (mean [SD] 40.6 [17.9] vs. 36.0 [12.5], P = .344). Frequency of hypocalcemia and vitamin D deficiency were also significantly high in children with SAM (P < .05). An inverse correlation was found between serum calcium and serum osteocalcin (r = -0.383, P < .05). Our results indicate that children with SAM have a higher bone resorption rate than children with normal nutrition status indicating compromised bone health.

Effects of simulated microgravity and vibration on osteoblast and osteoclast activity in cultured zebrafish scales.

Zebrafish cultured scales have been used effectively to study cellular and molecular responses of bone cells. In order to expose zebrafish scales to simulated microgravity (SMG) and/or vibration, we first determined via apoptosis staining whether cells of the scale survive in culture for two days and hence, we restricted our analyses to two-day durations. Next, we measured the effects of SMG and vibration on cell death, osteoclast tartrate-resistant acid phosphatase, and osteoblast alkaline phosphatase activity and on the number of Runx2a positive cells. We found that during the SMG treatment, osteoclast tartrate-resistant acid phosphatase activity increased on average, while the number of Runx2a positive cells decreased significantly. In contrast, SMG exposure caused a decrease in osteoblast activity. The vibration treatment showed an increase, on average, in the osteoblast alkaline phosphatase activity. This study demonstrates the effect of SMG and vibration on zebrafish scales and the effects of SMG on bone cells. We also show that zebrafish scales can be used to examine the effects of SMG on bone maintenance.

Influence of Occlusal Hypofunction on Alveolar Bone Healing in Rats.

The aim of this in vivo study was to investigate the effect of occlusal hypofunction on alveolar bone healing in the absence or presence of an enamel matrix derivative (EMD). A standardized fenestration defect over the root of the mandibular first molar in 15 Wistar rats was created. Occlusal hypofunction was induced by extraction of the antagonist. Regenerative therapy was performed by applying EMD to the fenestration defect. The following three groups were established: (a) normal occlusion without EMD treatment, (b) occlusal hypofunction without EMD treatment, and (c) occlusal hypofunction with EMD treatment. After four weeks, all animals were sacrificed, and histological (hematoxylin and eosin, tartrate-resistant acid phosphatase) as well as immunohistochemical analyses (periostin, osteopontin, osteocalcin) were performed. The occlusal hypofunction group showed delayed bone regeneration compared to the group with normal occlusion. The application of EMD could partially, but not completely, compensate for the inhibitory effects of occlusal hypofunction on bone healing, as evidenced by hematoxylin and eosin and immunohistochemistry for the aforementioned molecules. Our results suggest that normal occlusal loading, but not occlusal hypofunction, is beneficial to alveolar bone healing. Adequate occlusal loading appears to be as advantageous for alveolar bone healing as the regenerative potential of EMD.

Interrelationships between sarcopenia, bone turnover markers and low bone mineral density in patients on hemodialysis.

BACKGROUND: Hemodialysis (HD) patients are at risk for sarcopenia (SP) and bone loss, which may impact falls and bone fragility and lead to poor prognosis. Patients with HD and those with osteoporosis (OP) are still underdiagnosed and untreated. The aims of the present study were to evaluate the factors that affect bone mineral density (BMD) loss in HD patients, and explore traditional and novel approaches to manage chronic kidney disease-mineral-bone disorder (CKD-MBD). METHODS: Patients who underwent regular HD at the First Affiliated Hospital of Soochow University were retrospectively evaluated. According to the WHO osteoporosis criteria, patients were categorized into three groups: normal BMD, osteopenia, and osteoporosis. Demographic and clinical data, skeletal muscle mass, and bone turnover markers(BTM) were compared between the three groups. The correlation between bone density and muscle mass was calculated, and related risk factors were analyzed. RESULTS: This study enrolled 130 HD patients, 36 patients were diagnosed with sarcopenia (27.7%), 44 patients were diagnosed with osteopenia (33.8%), 19 patients were diagnosed with osteoporosis (14.6%), and 23 patients were diagnosed with osteosarcopenia (17.7%). The SMI was positively correlated with the BMD of the lumbar spine (r = 0.23, p < 0.01) and femoral neck (r = 0.22, p < 0.05). In ordinal logistic regression analysis, the odds ratio (OR) for low BMD was high for patients with sarcopenia (OR = 5.894, 95% CI 1.592-21.830, p < 0.01), older age (OR = 1.095, 95% CI 1.041-1.153, p < 0.001), higher TRACP-5b levels (OR = 1.597, 95% CI 1.230-2.072, p < 0.01), and lower 25-OH vitamin D levels (OR = 0.631, 95% CI 0.544-0.733, p < 0.001). CONCLUSION: The preservation of skeletal muscle mass could be important to prevent a BMD decrease in HD patients. Adequate intake of vitamin D and control of TRACP-5b levels will help reduce the occurrence and progression of osteopenia/sarcopenia in HD patients.