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Journal of Functional Biomaterials May 2024The aim of this study was to evaluate the effect of local administration of melatonin (MLT) on molecular biomarkers and calvaria bone critical defects in female rats...
The aim of this study was to evaluate the effect of local administration of melatonin (MLT) on molecular biomarkers and calvaria bone critical defects in female rats with or without osteoporosis, associated or not with a xenogeneic biomaterial. Forty-eight female rats were randomly divided into two groups: (O) ovariectomized and (S) placebo groups. After 45 days of osteoporosis induction, two critical-size defects (5 mm diameter) were created on the calvaria. The groups were subdivided according to the following treatment: (C) Clot, MLT, MLT associated with Bio-Oss (MLTBO), and Bio-Oss (BO). After 45 days, the defect samples were collected and processed for microtomography, histomorphometry, and biomolecular analysis (Col-I, BMP-2, and OPN). All animals had one femur harvested to confirm the osteoporosis. Microtomography analysis demonstrated a bone mineral density reduction in the O group. Regarding bone healing, the S group presented greater filling of the defects than the O group; however, in the O group, the defects treated with MLT showed higher mineral filling than the other treatments. There was no difference between the treatments performed in the S group ( = 0.05). Otherwise, O-MLT had neoformed bone higher than in the other groups ( = 0.05). The groups that did not receive biomaterial demonstrated lower levels of Col-I secretion; S-MLT and S-MLTBO presented higher levels of OPN, while O-C presented statistically lower results ( < 0.05); O-BO showed greater BMP-2 secretion ( < 0.05). In the presence of ovariectomy-induced osteoporosis, MLT treatment increased the newly formed bone area, regulated the inflammatory response, and increased OPN expression.
PubMed: 38786635
DOI: 10.3390/jfb15050124 -
Journal of Orthopaedic Surgery and... May 2024Elderly patients suffering from osteoporotic fractures are more susceptible to delayed union or nonunion, and their bodies then are in a state of low-grade chronic...
BACKGROUND
Elderly patients suffering from osteoporotic fractures are more susceptible to delayed union or nonunion, and their bodies then are in a state of low-grade chronic inflammation with decreased antioxidant capacity. Tanshinone IIA is widely used in treating cardiovascular and cerebrovascular diseases in China and has anti-inflammatory and antioxidant effects. We aimed to observe the antioxidant effects of Tanshinone IIA on mesenchymal stem cells (MSCs), which play important roles in bone repair, and the effects of local application of Tanshinone IIA using an injectable biodegradable hydrogel on osteoporotic fracture healing.
METHODS
MSCs were pretreated with or without different concentrations of Tanshinone IIA followed by HO treatment. Ovariectomized (OVX) C57BL/6 mice received a mid-shaft transverse osteotomy fracture on the left tibia, and Tanshinone IIA was applied to the fracture site using an injectable hydrogel.
RESULTS
Tanshinone IIA pretreatment promoted the expression of nuclear factor erythroid 2-related factor 2 and antioxidant enzymes, and inhibited HO-induced reactive oxygen species accumulation in MSCs. Furthermore, Tanshinone IIA reversed HO-induced apoptosis and decrease in osteogenic differentiation in MSCs. After 4 weeks of treatment with Tanshinone IIA in OVX mice, the bone mineral density of the callus was significantly increased and the biomechanical properties of the healed tibias were improved. Cell apoptosis was decreased and Nrf2 expression was increased in the early stage of callus formation.
CONCLUSIONS
Taken together, these results indicate that Tanshinone IIA can activate antioxidant enzymes to protect MSCs from HO-induced cell apoptosis and osteogenic differentiation inhibition. Local application of Tanshinone IIA accelerates fracture healing in ovariectomized mice.
Topics: Animals; Abietanes; Female; Mesenchymal Stem Cells; Apoptosis; Mice, Inbred C57BL; Fracture Healing; Ovariectomy; Mice; Antioxidants; Hydrogen Peroxide; Osteogenesis; Osteoporotic Fractures
PubMed: 38783358
DOI: 10.1186/s13018-024-04793-x -
Veterinary Journal (London, England :... Jun 2024General anesthesia and surgical stress can suppress the immunological response by acting both directly on the immune system and indirectly on the...
General anesthesia and surgical stress can suppress the immunological response by acting both directly on the immune system and indirectly on the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system. Disturbance of the immune system during the perioperative period can lead to complications such as wound-healing disorders and infections up to sepsis. Effectiveness of acupuncture in regulating the immune function by increasing leukocyte numbers and inhibiting inflammatory response has been proven. This study aimed to explore the impact of electroacupuncture (EAP) on the dynamic balance of the immune system and immune cell populations in dogs undergoing surgery. Twelve healthy bitches scheduled for elective ovariectomy were divided into two groups according to whether (EAP, n=6) or not (CTR, n=6) a peri-operative electroacupuncture treatment was performed. Levels of leukocytes (neutrophils, monocytes, T- and B-cells) and immunoglobulins M (IgM) and A (IgA) were measured in blood samples collected before (T0), 1 h (T1) and 2.5 h (T2) after anesthesia induction. Leukocytes count decreased from T0 to T1 in both groups and restored within 1.5 h in EAP group whereas remained significantly lower in CTR group (P<0.02). In particular, neutrophils and monocytes increased in dogs receiving EAP (P<0.01) while T-cells decreased in CTR group (P<0.04) at T2. B-cells and cytotoxic T-cells decreased in EAP dogs (P<0.04) at T2. No differences in helper T-cells, IgM and IgA levels were recorded between groups and over time. Our results suggest a modulatory effect of EAP on the immune system which is early expressed on neutrophils, monocytes and T-cells.
Topics: Animals; Dogs; Electroacupuncture; Female; Pilot Projects; Ovariectomy; Leukocyte Count; Immunoglobulin A; Immunoglobulin M
PubMed: 38782236
DOI: 10.1016/j.tvjl.2024.106140 -
Biomedicine & Pharmacotherapy =... Jun 2024Stress cardiomyopathy (SCM) is associated with cardiovascular mortality rates similar to acute coronary syndrome. Myocardial injuries driven by inflammatory mechanisms...
Stress cardiomyopathy (SCM) is associated with cardiovascular mortality rates similar to acute coronary syndrome. Myocardial injuries driven by inflammatory mechanisms may in part account for the dismal prognosis of SCM. Currently, no inflammation-targeted therapies are available to mitigate SCM-associated myocardial injuries. In this study, acute catecholamine surge-induced SCM was modeled by stimulating the ovariectomized (OVX) mice with isoproterenol (ISO). The effects of ginsenoside Rb1 (Rb1) on SCM-associated myocardial injuries were assessed in the OVX-ISO compound mice. RAW 264.7 macrophages stimulated with calf thymus DNA (ctDNA) or STING agonist DMXAA were adopted to further understand the anti-inflammatory mechanisms of Rb1. The results show that estrogen deprivation increases the susceptibility to ISO-induced myocardial injuries. Rb1 mitigates myocardial injuries and attenuates cardiomyocyte necrosis as well as myocardial inflammation in the OVX-ISO mice. Bioinformatics analysis suggests that cytosolic DNA-sensing pathway is closely linked with ISO-triggered inflammatory responses and cell death in the heart. In macrophages, Rb1 lowers ctDNA-stimulated production of TNF-α, IL-6, CCL2 and IFN-β. RNA-seq analyses uncover that Rb1 offsets DNA-stimulated upregulation in multiple inflammatory response pathways and cytosolic DNA-sensing pathway. Furthermore, Rb1 directly mitigates DMXAA-stimulated STING activation and inflammatory responses in macrophages. In conclusion, the work here demonstrates for the first time that Rb1 protects against SCM-associated myocardial injuries in part by counteracting acute ISO stress-triggered cardiomyocyte necrosis and myocardial inflammation. Moreover, by evidencing that Rb1 downregulates cytosolic DNA-sensing machineries in macrophages, our findings warrant further investigation of therapeutic implications of the anti-inflammatory Rb1 in the treatment of SCM.
Topics: Animals; Mice; Ginsenosides; RAW 264.7 Cells; Female; Membrane Proteins; Macrophage Activation; Isoproterenol; Mice, Inbred C57BL; Macrophages; Catecholamines; Takotsubo Cardiomyopathy; Anti-Inflammatory Agents; Ovariectomy; Myocardium; Myocytes, Cardiac
PubMed: 38776673
DOI: 10.1016/j.biopha.2024.116794 -
Theriogenology Aug 2024The vaginal microbiota of the queen (i.e., female cat) has never been described using culture independent methods. The objectives of the present research were to...
The vaginal microbiota of the queen (i.e., female cat) has never been described using culture independent methods. The objectives of the present research were to describe the vaginal microbiota of healthy domestic shorthair queens using both 16S rRNA sequencing and culture, and to assess the effects of age, living environment, and reproductive season on its composition. Thirty queens undergoing elective ovariectomy were included in the study. The vaginal samples were collected just before surgery, from animals under general anaesthesia. Two consecutive mini-swabs were introduced in the queens' vaginal tract. A preliminary study with 10 healthy queens aimed to negate sampling order's effect. Two consecutive samples for sequencing (5 queens, 10 swabs) and culture (5 queens, 10 swabs) were collected, confirming a match (100 % in culture, Bray-Curtis P = 0.96 in sequencing). The experiment included 20 queens that were prospectively grouped based on age (prepubertal N = 10, adult N = 10), living environment (indoor N = 10, outdoor N = 10), and time of the year, whether during the reproductive season (N = 10) or during seasonal anoestrous (N = 10). Bacteria were identified through metataxonomic analysis, amplifying the V1-V2 regions of 16S rRNA gene, and through standard culture followed by MALDI-TOF MS. The feline vaginal microbiota is dominated by Proteobacteria, Firmicutes, Bacteroidota, and Actinobacteria. Escherichia-Shigella, Streptococcus, and Pasteurella were the most abundant genera. Although culture underestimated bacterial richness and diversity compared to sequencing, Escherichia and Streptococcus were the most isolated bacteria. No bacterial growth was observed in 15 % of samples (N = 3/20), whereas growth of one or two bacterial species was observed in 64.7 % (N = 11/17) and 35.3 % (N = 6/17) of cases, respectively. No differences in terms of alpha (Kruskal-Wallis rank sum test P = 0.65) and beta diversity (Bray-Curtis, Unweighted and Weighted UniFrac analyses P > 0.5) were observed. Although a difference in alpha diversity based on phylogenetic tree (P = 0.02) was detected between indoor and outdoor queens. In conclusion, mixed and monoculture of Escherichia coli, Streptococcus canis, Staphylococcus felis, and Enterococcus spp. are normal findings within the cat vagina. Age and reproductive season do not influence the feline vaginal microbiota, whereas further research is needed to elucidate the role of the living environment.
Topics: Animals; Cats; Female; Vagina; Microbiota; Bacteria; RNA, Ribosomal, 16S; Seasons
PubMed: 38772246
DOI: 10.1016/j.theriogenology.2024.05.021 -
World Journal of Diabetes May 2024Visceral obesity is increasingly prevalent among adolescents and young adults and is commonly recognized as a risk factor for type 2 diabetes. Estrogen [17β-estradiol...
BACKGROUND
Visceral obesity is increasingly prevalent among adolescents and young adults and is commonly recognized as a risk factor for type 2 diabetes. Estrogen [17β-estradiol (E2)] is known to offer protection against obesity diverse me-chanisms, while its specific effects on visceral adipose tissue (VAT) remain to be fully elucidated.
AIM
To investigate the impact of E2 on the gene expression profile within VAT of a mouse model of prediabetes.
METHODS
Metabolic parameters were collected, encompassing body weight, weights of visceral and subcutaneous adipose tissues (VAT and SAT), random blood glucose levels, glucose tolerance, insulin tolerance, and overall body composition. The gene expression profiles of VAT were quantified utilizing the Whole Mouse Genome Oligo Microarray and subsequently analyzed through Agilent Feature Extraction software. Functional and pathway analyses were conducted employing Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses, respectively.
RESULTS
Feeding a high-fat diet (HFD) moderately increased the weights of both VAT and SAT, but this increase was mitigated by the protective effect of endogenous E2. Conversely, ovariectomy (OVX) led to a significant increase in VAT weight and the VAT/SAT weight ratio, and this increase was also reversed with E2 treatment. Notably, OVX diminished the expression of genes involved in lipid metabolism compared to HFD feeding alone, signaling a widespread reduction in lipid metabolic activity, which was completely counteracted by E2 administration. This study provides a comprehensive insight into E2's local and direct protective effects against visceral adiposity in VAT at the gene level.
CONCLUSION
In conclusion, the present study demonstrated that the HFD-induced over-nutritional challenge disrupted the gene expression profile of visceral fat, leading to a universally decreased lipid metabolic status in E2 deficient mice. E2 treatment effectively reversed this condition, shedding light on the mechanistic role and therapeutic potential of E2 in combating visceral obesity.
PubMed: 38766434
DOI: 10.4239/wjd.v15.i5.988 -
Research Square May 2024In multiple myeloma (MM), increased osteoclast differentiation leads to the formation of osteolytic lesions in most MM patients. Bisphosphonates, such as zoledronic acid...
In multiple myeloma (MM), increased osteoclast differentiation leads to the formation of osteolytic lesions in most MM patients. Bisphosphonates, such as zoledronic acid (ZA), are used to ameliorate bone resorption, but due to risk of serious side effects as well as the lack of repair of existing lesions, novel anti-bone resorption agents are required. Previously, the absence of osteolytic lesions in MM was strongly associated with elevated levels of cystatin M/E (CST6), a cysteine protease inhibitor, secreted by MM cells. In this study, both MM- and ovariectomy (OVX)-induced osteoporotic mouse models were used to compare the effects of recombinant mouse CST6 (rmCst6) and ZA on preventing bone loss. μCT showed that rmCst6 and ZA had similar effects on improving percent bone volume, and inhibited differentiation of non-adherent bone marrow cells into mature osteoclasts. Single-cell RNA sequencing showed that rmCst6 and not ZA treatment reduced bone marrow macrophage percentage in the MM mouse model compared to controls. Protein and mRNA arrays showed that both rmCst6 and ZA significantly inhibit OVX-induced expression of inflammatory cytokines. For OVX mice, ERα protein expression in bone was brought to sham surgery level by only rmCst6 treatments. rmCst6 significantly increased mRNA and protein levels of ERα and significantly increased total intracellular estrogen concentrations for osteoclast precursor cell cultures. Based on these results, we conclude that CST6 improves MM or OVX bone loss models by increasing the expression of estrogen receptors as well as the intracellular estrogen concentration in osteoclast precursors, inhibiting their maturation.
PubMed: 38766009
DOI: 10.21203/rs.3.rs-4313179/v1 -
Stem Cell Research & Therapy May 2024The aim of this study was to evaluate potential synergistic effects of a single, local application of human umbilical cord MSC-derived sEVs in combination with a low...
BACKGROUND
The aim of this study was to evaluate potential synergistic effects of a single, local application of human umbilical cord MSC-derived sEVs in combination with a low dose of recombinant human rhBMP-2 to promote the regeneration of a metaphyseal femoral defect in an osteoporotic rat model.
METHODS
6 weeks after induction of osteoporosis by bilateral ventral ovariectomy and administration of a special diet, a total of 64 rats underwent a distal femoral metaphyseal osteotomy using a manual Gigli wire saw. Defects were stabilized with an adapted Y-shaped mini-locking plate and were subsequently treated with alginate only, or alginate loaded with hUC-MSC-sEVs (2 × 10), rhBMP-2 (1.5 µg), or a combination of sEVs and rhBMP-2 (n = 16 for each group). 6 weeks post-surgery, femora were evaluated by µCT, descriptive histology, and biomechanical testing.
RESULTS
Native radiographs and µCT analysis confirmed superior bony union with callus formation after treatment with hUC-MSC-sEVs in combination with a low dose of rhBMP-2. This finding was further substantiated by histology, showing robust defect consolidation 6 weeks after treatment. Torsion testing of the explanted femora revealed increased stiffness after application of both, rhBMP-2 alone, or in combination with sEVs, whereas torque was only significantly increased after treatment with rhBMP-2 together with sEVs.
CONCLUSION
The present study demonstrates that the co-application of hUC-MSC-sEVs can improve the efficacy of rhBMP-2 to promote the regeneration of osteoporotic bone defects.
Topics: Animals; Bone Morphogenetic Protein 2; Recombinant Proteins; Osteoporosis; Rats; Female; Humans; Femur; Umbilical Cord; Extracellular Vesicles; Bone Regeneration; Rats, Sprague-Dawley; Transforming Growth Factor beta; Disease Models, Animal; X-Ray Microtomography; Mesenchymal Stem Cells
PubMed: 38764077
DOI: 10.1186/s13287-024-03755-8 -
Brazilian Oral Research 2024The aim of this systematic review was to answer the following question: "Does alendronate, a nitrogen-containing bisphosphonate, improve or impair alveolar socket...
The aim of this systematic review was to answer the following question: "Does alendronate, a nitrogen-containing bisphosphonate, improve or impair alveolar socket healing after tooth extraction in animal models"? To this end, a systematic review of the literature was carried out in PubMed, Scopus, LILACS, Web of Science, as well as in the gray literature up to May 2023. Preclinical studies that evaluated alveolar healing after tooth extraction and the intake of sodium alendronate compared with placebo were included. Two investigators were responsible for screening the articles independently, extracting the data, and assessing their quality through the SYRCLE's RoB tool for randomized trials in animal studies. The study selection process, study characteristics, risk of bias in studies, impact of alendronate on bone healing, and certainty of evidence were described in text and table formats. Methodological differences among the studies were restricted to the synthesis methods. The synthesis of qualitative results followed the Synthesis Without Meta-analysis (SWiM) reporting guideline. From the 19 included studies, five were considered to have low risk, three were of unclear risk, and eleven presented a high risk of bias. The studies were considered heterogeneous regarding alendronate posology, including its dosage and route of administration. Furthermore, a variety of animal species, different age ranges, diverse teeth extracted, and exposure or not to ovariectomy contributed to the lack of parity of the selected studies. Our results indicated that alendronate monotherapy negatively affects the early phase of wound healing after tooth extraction in preclinical studies, suggesting that the bone resorption process after tooth extraction in animals treated with alendronate might impair the bone healing process of the extraction socket. In conclusion, alendronate administration restrains bone resorption, thereby delaying alveolar socket healing . Future studies should be conducted to validate these findings and to better understand the effects of alendronate therapy on oral tissues.
Topics: Alendronate; Tooth Extraction; Animals; Wound Healing; Tooth Socket; Bone Density Conservation Agents
PubMed: 38747825
DOI: 10.1590/1807-3107bor-2024.vol38.0038 -
Research Square May 2024Osteoporosis is incurable because there are no dual antiresorptive and anabolic therapeutic agents that can be administered long-term. The most widely used...
Osteoporosis is incurable because there are no dual antiresorptive and anabolic therapeutic agents that can be administered long-term. The most widely used antiresorptive agents, bisphosphonates (BPs), also inhibit bone formation and thus have limited effect in preventing osteoporotic fracture. Hydroxychloroquine (HCQ), which is used to treat rheumatoid arthritis, prevents the lysosomal degradation of TNF receptor-associated factor 3 (TRAF3), an NF-κB adaptor protein that limits bone resorption and maintains bone formation. We attempted to covalently link HCQ to a hydroxyalklyl BP (HABP) with anticipated low antiresorptive activity, to target delivery of HCQ to bone to test if this targeting increases its efficacy to prevent TRAF3 degradation in the bone microenvironment and thus reduce bone resorption and increase bone formation, while reducing its systemic side effects. Unexpectedly, HABP-HCQ was found to exist as a salt in aqueous solution, composed of a protonated HCQ cation and a deprotonated HABP anion. Nevertheless, it inhibited osteoclastogenesis, stimulated osteoblast differentiation, and increased TRAF3 protein levels in vitro. HABP-HCQ significantly inhibited both osteoclast formation and bone marrow fibrosis in mice given multiple daily PTH injections. In contrast, HCQ inhibited fibrosis, but not osteoclast formation, while the HABP alone inhibited osteoclast formation, but not fibrosis, in the mice. HABP-HCQ, but not HCQ, prevented trabecular bone loss following ovariectomy in mice and, importantly, increased bone volume in ovariectomized mice with established bone loss because HABP-HCQ increased bone formation and decreased bone resorption parameters simultaneously. In contrast, HCQ increased bone formation, but did not decrease bone resorption parameters, while HABP also restored the bone lost in ovariectomized mice, but it inhibited parameters of both bone resorption and formation. Our findings suggest that the combination of HABP and HCQ could have dual antiresorptive and anabolic effects to prevent and treat osteoporosis.
PubMed: 38746138
DOI: 10.21203/rs.3.rs-4237258/v1