Effectiveness of two scrub methods with different chlorhexidine combinations for surgical field antisepsis in cats.

Objective: Assessing effectiveness of circular (CM) and linear (LM) scrub methods using 3 different combinations of chlorhexidine in surgical field antisepsis in cats. Animals and procedure: Surgical field antisepsis was applied with 2 scrub methods (CM and LM) and 3 different chlorhexidine combinations (A1, A2, and A3) in 51 female cats undergoing ovariectomy. Sterile swabs collected from the surgical field pre- and post-antisepsis were inoculated in the laboratory and colony-forming units (CFU/mL) were quantified. Results: Following the application of antisepsis, the number of positive samples decreased in all groups (P < 0.05) when using both CM and LM, except for CM in the A1 group (P = 0.063). The CFU/mL counts also decreased after antisepsis with both CM and LM in all groups (P < 0.05). A high reduction in CFU/mL counts was observed after antisepsis with both CM and LM in all groups, but no significant differences were observed between the 2 scrub methods (P > 0.05). Conclusion and clinical relevance: Surgical field antisepsis in cats with CM and LM scrub methods, using 2% chlorhexidine combined with 70% ethyl or 70% isopropyl alcohol, or 1% chlorhexidine combined with 70% ethyl alcohol, can effectively reduce the bacterial load on the skin.

Efficacité de deux méthodes de désinfection avec différentes combinaisons de chlorhexidine pour l'antisepsie du champ opératoire chez le chat. Objectif: Évaluation de l'efficacité des méthodes de désinfection par mouvements circulaires (CM) et linéaires (LM) utilisant 3 combinaisons différentes de chlorhexidine dans l'antisepsie du champ opératoire chez le chat. Animaux et procédure: Une antisepsie chirurgicale sur le terrain a été appliquée avec 2 méthodes de désinfection (CM et LM) et 3 combinaisons différentes de chlorhexidine (A1, A2 et A3) chez 51 chattes subissant une ovariectomie. Des écouvillons stériles prélevés sur le champ opératoire avant et après l'antisepsie ont été inoculés en laboratoire et les unités formant des colonies (UFC/mL) ont été quantifiées. Résultats: À la suite de l'application de l'antisepsie, le nombre d'échantillons positifs a diminué dans tous les groupes (P < 0,05) lors de l'utilisation à la fois de CM et de LM, à l'exception du CM dans le groupe A1 (P = 0,063). Le nombre d'UFC/mL a également diminué après antisepsie avec CM et LM dans tous les groupes (P < 0,05). Une forte réduction du nombre d'UFC/mL a été observée après antisepsie avec CM et LM dans tous les groupes, mais aucune différence significative n'a été observée entre les 2 méthodes de désinfection (P > 0,05). Conclusion et pertinence clinique: L'antisepsie chirurgicale sur le terrain chez les chats avec les méthodes de désinfection CM et LM, utilisant 2 % de chlorhexidine combinée à 70 % d'alcool éthylique ou 70 % d'alcool isopropylique, ou 1 % de chlorhexidine combinée à 70 % d'alcool éthylique, peut réduire efficacement la charge bactérienne sur la peau.(Traduit par Dr Serge Messier).

Effect of surgery on oxidative stress and endogenous tocopherol concentrations in juvenile female dogs.

BACKGROUND: Surgery such as ovariectomy causes an inflammatory and oxidative stress. This study was designed to evaluate endogenous tocopherol levels in response to surgical oxidative stress induced by abdominal surgery (ovariectomy) in thirty-two juvenile female dogs. The dogs received meloxicam before surgery (0.2 mg/kg SC) and after surgery (0.1 mg/kg OS every 24 h), 0.03 mg/kg of atropine sulfate (IM), and propofol 4 mg/kg intravenously (IV). General anesthesia was maintained with sevoflurane. Physiological, hematological and biochemical parameters, malondialdehyde (MDA) and α-, δ-, γ-tocopherols were evaluated at baseline, 36 and 48 h after surgery. RESULTS: The physiological parameters remained within normal ranges. Blood glucose concentration increased, while the albumin levels decreased after surgery. Rescue analgesia was not required. MDA levels increased above the baseline at 36 and 48 h after surgery (P < 0.001). The α-, δ-, and γ-tocopherol concentrations decreased from baseline at 36 and 48 h after surgery (P < 0.001). CONCLUSIONS: Surgery in juvenile female dogs revealed oxidative, increased MDA concentrations, reduced tocopherol levels, and had a clinically insignificant influence on homeostasis.

LAMN port-site metastasis after laparoscopic oophorectomy for a presumed ovarian tumour treated with CRS and HIPEC.

Low-grade appendiceal mucinous neoplasm (LAMN) may culminate as a mucin-secreting disease known as pseudomyxoma peritonei (PMP). Once the diagnosis of LAMN and PMP is made, cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS and HIPEC) are indicated.Herein, we present a female patient in her 50s who was diagnosed with an ovarian mass for which she underwent laparoscopic oophorectomy. As the pathology of the ovary showed a tumour of gastrointestinal origin, she then underwent CRS and HIPEC with a final pathology of LAMN. Six weeks later, a mucinous lesion confined to the abdominal wall was detected on a postoperative CT. Suspected for port-site metastasis at the laparoscopic trocar site, we treated this lesion using the same principles of treatment as the intra-abdominal disease. The abdominal wall mass was surgically resected, and the cavity created was irrigated with mitomycin C. On 30 months of follow-up, the patient had no evidence of disease.

Oxidative stress in relation to serotonin under general anaesthesia in dogs undergoing ovariectomy.

Abdominal surgery such as ovariectomy is a traumatic event that can cause oxidative stress. The aim of the present study was to evaluate the concentration of serotonin in relation to ovariectomy-induced oxidative stress in dogs undergoing general anesthesia. Thirty-two female dogs, under general anesthesia, received meloxicam before surgery (0.2 mgkg-1 SC) and after surgery (0.1 mgkg-1 OS every 24 h). The physiological, hematological, and biochemical parameters: glycemia, aspartate transaminase (AST), alanine aminotransferase (ALT), total protein, albumin and BUN were evaluated. Oxidative stress was determined by malondialdehyde (MDA) assay, catalase (CAT), superoxide dismutase (SOD), myeloperoxidase (MPO) and butyrylcholinesterase (BuChe) at baseline, 36 and 48 h after the last administration of meloxicam. Serotonin (5-HT) concentration was also evaluated at baseline, 36 and 48 h after the last administration of meloxicam. Responses to surgical stimulus were evaluated. Physiological and hematological parameters they fell within the normal ranges for anesthetized dogs. Glycemia increased, albumin levels decreased after surgery. No rescue analgesia was required. MDA and 5-HT concentrations significantly increased from the baseline at 36 and 48 h after surgery (p < .001). 5-HT levels could be used as an indicator for oxidative stress induced by surgery and it might be employed for objectively quantifying the well-being of the surgical patient.

[Effect and mechanism of Gusong Qianggu Decoction on reducing bone loss in ovariectomized mice by targeting endoplasmic reticulum stress-induced apoptosis of osteocytes].

This study aims to investigate the role and mechanism of Gusong Qianggu Decoction(GSQG) in attenuating bone loss in ovariectomized mice by targeting the endoplasmic reticulum stress(ERS)-induced apoptosis of osteocytes. After the modeling of osteoporosis in mice with bilateral ovary removal(OVX), 60 mice were randomized by the random number method into six groups: sham,model, low-, medium-, and high-dose GSQG(GSQG-L, GSQG-M, and GSQG-H, respectively), and estradiol(E_2), with 10 mice in each group. The mice in each group were administrated with corresponding drugs by gavage one month after surgery and the administration lasted for 3 months. Enzyme-linked immunosorbent assay(ELISA) was employed to determine the serum levels of osteocalcin(OCN), procollagen type Ⅰ N-terminal propeptide(PINP), carboxy-terminal cross-linked telopeptide of type Ⅰ collagen(CTX),and anti-tartarte acid phosphatase 5b(TRAcP-5b). Micro-CT was employed to observe the changes in bone microstructure of the distal femur. Hematoxylin-eosin(HE) staining was employed to observe the morphology of the bone tissue. RT-qPCR was conducted to determine the m RNA levels of tibial stem osteogenesis-associated genes [type Ⅰ collagen(Col-Ⅰ), alkaline phosphatase(ALP), Runtrelated transcription factor-2(Runx2), bone sialoprotein(BSP), and OCN] and bone-breaking related genes [tartrate-resistant acid phosphatase(TRAP), nuclear factor-activated T cell 1(NFATc1), and cathepsin K(CATK)]. TUNEL staining and immunohistochemistry were employed to detect the apoptosis of osteoblasts. Western blot was employed to measure the expression of ERS-related proteins glucose-regulated protein 78( Grp78), protein kinase RNA-like endoplasmic reticulum kinase( PERK), phosphorylated PERK(p-PERK),eukaryotic translation initiation factor 2 alpha(eIF2α), phosphorylated e IF2α(p-eIF2α), inositol-requiring enzyme 1 alpha(IRE1α), phosphorylated IRE1α(p-IRE1α), and activating transcription factor 6(ATF6) in the proximal tibial bone tissue. The results showed that GSQG significantly recovered the levels of OCN, PINP, TRAc P-5b, and CTX in the serum of ovariectomized mice, and Micro-CT showed that GSQG improved the bone microstructure of distal femur in a dose-dependent manner. Compared with the model group, GSQG widened and increased the bone trabeculae, restored the reticular structure with neat arrangement and enlarged interstitial gaps, and reduced the number of TUNEL-positive cells(P<0. 05, P<0. 01). Furthermore, GSQG down-regulated the expression levels of cysteine aspartate protease-3( caspase-3) and factor Bcl-2-associated X protein( Bax)(P< 0. 05,P<0. 01) and up-regulated the expression level of Bcl-2(P<0. 05, P<0. 01). The GSQG groups showed up-regulated m RNA levels of Col-Ⅰ, ALP, Runx2, BSP, and OCN(P< 0. 01) and down-regulated m RNA levels of TRAP, NFATc1, and CATK(P< 0. 05,P<0. 01). In addition, GSQG, especially GSQG-H, down-regulated the protein levels of Grp78, p-PERK, p-eIF2, p-IRE1α, and ATF6(P< 0. 05, P< 0. 01). In conclusion, GSQG can inhibit the apoptosis of osteocytes by inhibiting the Grp78/PERK/e IF2α/IRE1α/ATF6 signaling pathway in the proximal tibia tissue, thus reducing bone loss in ovariectomized mice.

Silkworm (Bombyx mori L.) Has Beneficial Effects on Menopausal Symptoms by Enhancing Estrogen Receptor Signaling in Ovariectomized Mice.

Existing hormone replacement therapy for menopause has drawbacks, necessitating new treatment agents. Silkworms have demonstrated estrogenic properties, offering promising alternatives. We assessed the therapeutic effects of freeze-dried silkworm powder (SWP) on menopausal symptoms using an ovariectomized (OVX) mouse model. The experimental design comprised a sham surgery group (Sham), an OVX control group, a low-dose SWP group post-OVX (80 mg/kg, OVX-SWP-L), a high-dose SWP group post-OVX (160 mg/kg, OVX-SWP-H), and an estradiol treatment group post-OVX (OVX-E2). Treatments were administered orally thrice weekly over eight weeks; body weight was monitored weekly. The SWP-treated groups (SWP-L and SWP-H) exhibited less weight gain and increased uterine thickness than the OVX control. Molecular analyses demonstrated that SWP significantly enhanced the phosphorylation of estrogen receptor alpha (ERα), ERK, and AKT. Furthermore, biochemical assays revealed reduced serum neutral lipids across all SWP treatment groups. Notably, HDL-cholesterol levels were significantly increased in the SWP-L group compared to the OVX group. Serum estradiol concentrations were elevated in all the SWP groups, with significant increases in the high-dose group. These findings indicate that SWP may promote the activation of estrogen receptor signaling and improve symptoms associated with estrogen deficiency during menopause.

Effectiveness of desertliving cistanche in managing hyperlipidemic osteoporosis in ovariectomized rats through the PI3K/AKT signaling pathway.

BACKGROUND: To aim of this study is to assess the mechanism through which Desertliving Cistanche modulates the PI3K/AKT signaling pathway in the treatment of hyperlipidemic osteoporosis in ovariectomized rats. METHODS: We randomly assigned specific-pathogen-free (SPF) rats into five groups (n = 10 per group). The normal control group received a standard diet, while the model group, atorvastatin group, diethylstilbestrol group, and treatment group were fed a high-fat diet. Four weeks later, bilateral ovariectomies were conducted, followed by drug interventions. After six weeks of treatment, relevant indicators were compared and analyzed. RESULTS: Compared to the normal control group, rats in the model group exhibited blurred trabecular morphology, disorganized osteocytes, significantly elevated levels of bone-specific alkaline phosphatase (BALP), bone Gla-protein (BGP), total cholesterol (TC), tumor necrosis factor-α (TNF-α), and receptor activator of NF-κB ligand (RANKL). Also, the model group revealed significantly reduced levels of ultimate load, fracture load, estradiol (E2), bone mineral density (BMD), osteoprotegerin (OPG), and phosphoinositide 3-kinase (PI3K) and protein kinase B (Akt) in femoral tissue. The atorvastatin group presented with higher TC and TNF-α levels compared to the normal control group. Conversely, the treatment group demonstrated enhanced trabecular morphology, denser structure, smaller bone marrow cavities, and reduced BALP, BGP, TC, TNF-α, and RANKL levels. Furthermore, the treatment group exhibited higher levels of E2, BMD, OPG, and PI3K and Akt in bone tissue compared to the model group. The treatment group also had lower TC and TNF-α levels than the atorvastatin group. Biomechanical analysis indicated that after administration of Desertliving Cistanche, the treatment group had reduced body mass, increased ultimate and fracture load of the femur, denser bone structure, smaller bone marrow cavities, and altered periosteal arrangement compared to the model group. CONCLUSION: Our study revealed that Desertliving Cistanche demonstrated significant efficacy in preventing and treating postmenopausal hyperlipidemic osteoporosis in rats.

Osteoblast-specific down-regulation of NLRP3 inflammasome by aptamer-functionalized liposome nanoparticles improves bone quality in postmenopausal osteoporosis rats.

Rationale: NLRP3 inflammasome is critical in the development and progression of many metabolic diseases driven by chronic inflammation, but its effect on the pathology of postmenopausal osteoporosis (PMOP) remains poorly understood. Methods: We here firstly examined the levels of NLRP3 inflammasome in PMOP patients by ELISA. Then we investigated the possible mechanisms underlying the effect of NLRP3 inflammasome on PMOP by RNA sequencing of osteoblasts treated with NLRP3 siRNA and qPCR. Lastly, we accessed the effect of decreased NLRP3 levels on ovariectomized (OVX) rats. To specifically deliver NLRP3 siRNA to osteoblasts, we constructed NLRP3 siRNA wrapping osteoblast-specific aptamer (CH6)-functionalized lipid nanoparticles (termed as CH6-LNPs-siNLRP3). Results: We found that the levels of NLRP3 inflammasome were significantly increased in patients with PMOP, and were negatively correlated with estradiol levels. NLRP3 knock-down influenced signal pathways including immune system process, interferon signal pathway. Notably, of the top ten up-regulated genes in NLRP3-reduced osteoblasts, nine genes (except Mx2) were enriched in immune system process, and five genes were related to interferon signal pathway. The in vitro results showed that CH6-LNPs-siNLRP3 was relatively uniform with a dimeter of 96.64 ± 16.83 nm and zeta potential of 38.37 ± 1.86 mV. CH6-LNPs-siNLRP3 did not show obvious cytotoxicity and selectively delivered siRNA to bone tissue. Moreover, CH6-LNPs-siNLRP3 stimulated osteoblast differentiation by activating ALP and enhancing osteoblast matrix mineralization. When administrated to OVX rats, CH6-LNPs-siNLRP3 promoted bone formation and bone mass, improved bone microarchitecture and mechanical properties by decreasing the levels of NLRP3, IL-1ß and IL-18 and increasing the levels of OCN and Runx2. Conclusion: NLRP3 inflammasome may be a new biomarker for PMOP diagnosis and plays a key role in the pathology of PMOP. CH6-LNPs-siNLRP3 has potential application for the treatment of PMOP.

Ginkgetin attenuates bone loss in OVX mice by inhibiting the NF-κB/IκBα signaling pathway.

Background: Osteoporosis is a disease associated with bone resorption, characterized primarily by the excessive activation of osteoclasts. Ginkgetin is a compound purified from natural ginkgo leaves which has various biological properties, including anti-inflammation, antioxidant, and anti-tumor effects. This study investigated the bone-protective effects of ginkgetin in ovariectomized (OVX) mice and explored their potential signaling pathway in inhibiting osteoclastogenesis in a mouse model of osteoporosis. Methods: Biochemical assays were performed to assess the levels of Ca, ALP, and P in the blood. Micro CT scanning was used to evaluate the impact of ginkgetin on bone loss in mice. RT-PCR was employed to detect the expression of osteoclast-related genes (ctsk, c-fos, trap) in their femoral tissue. Hematoxylin and eosin (H&E) staining was utilized to assess the histopathological changes in femoral tissue due to ginkgetin. The TRAP staining was used to evaluate the impact of ginkgetin osteoclast generation in vivo. Western blot analysis was conducted to investigate the effect of ginkgetin on the expression of p-NF-κB p65 and IκBα proteins in mice. Results: Our findings indicate that ginkgetin may increase the serum levels of ALP and P, while decreasing the serum level of Ca in OVX mice. H&E staining and micro CT scanning results suggest that ginkgetin can inhibit bone loss in OVX mice. The TRAP staining results showed ginkgetin suppresses the generation of osteoclasts in OVX mice. RT-PCR results demonstrate that ginkgetin downregulate the expression of osteoclast-related genes (ctsk, c-fos, trap) in the femoral tissue of mice, and this effect is dose-dependent. Western blot analysis results reveal that ginkgetin can inhibit the expression of p-NF-κB p65 and IκBα proteins in mice. Conclusion: Ginkgetin can impact osteoclast formation and activation in OVX mice by inhibiting the NF-κB/IκBα signaling pathway, thereby attenuating bone loss in mice.

Impdh2 deficiency suppresses osteoclastogenesis through mitochondrial oxidative phosphorylation and alleviates ovariectomy-induced osteoporosis.

Abnormalities in osteoclastic generation or activity disrupt bone homeostasis and are highly involved in many pathologic bone-related diseases, including rheumatoid arthritis, osteopetrosis, and osteoporosis. Control of osteoclast-mediated bone resorption is crucial for treating these bone diseases. However, the mechanisms of control of osteoclastogenesis are incompletely understood. In this study, we identified that inosine 5'-monophosphate dehydrogenase type II (Impdh2) positively regulates bone resorption. By histomorphometric analysis, Impdh2 deletion in mouse myeloid lineage cells (Impdh2LysM-/- mice) showed a high bone mass due to the reduced osteoclast number. qPCR and western blotting results demonstrated that the expression of osteoclast marker genes, including Nfatc1, Ctsk, Calcr, Acp5, Dcstamp, and Atp6v0d2, was significantly decreased in the Impdh2LysM-/- mice. Furthermore, the Impdh inhibitor MPA treatment inhibited osteoclast differentiation and induced Impdh2-cytoophidia formation. The ability of osteoclast differentiation was recovered after MPA deprivation. Interestingly, genome-wide analysis revealed that the osteoclastic mitochondrial biogenesis and functions, such as oxidative phosphorylation, were impaired in the Impdh2LysM-/- mice. Moreover, the deletion of Impdh2 alleviated ovariectomy-induced bone loss. In conclusion, our findings revealed a previously unrecognized function of Impdh2, suggesting that Impdh2-mediated mechanisms represent therapeutic targets for osteolytic diseases.

Caloric and time restriction diets improve acute kidney injury in experimental menopausal rats: role of silent information regulator 2 homolog 1 and transforming growth factor beta 1.

BACKGROUND: Estrogen has a protective impact on acute kidney injury (AKI); moreover, reducing the daily intake of calories impedes developing diseases. The present study aimed to determine the effects of calorie restriction (CR) and time restriction (TR) diets on the expression of silent information regulator 2 homolog 1 (SIRT1), transforming growth factor beta 1 (TGF-ß1), and other indicators in the presence and absence of ovaries in AKI female rats. METHODS: The female rats were divided into two groups, ovariectomized (OVX) and sham, and were placed on CR and TR diets for eight weeks; afterward, AKI was induced by injecting glycerol, and kidney injury indicators and biochemical parameters were measured before and after AKI. RESULTS: After AKI, the levels of urine albumin excretion rate, urea, and creatinine in serum, and TGF-ß1 increased, while creatinine clearance and SIRT1 decreased in kidney tissue. CR improved kidney indicators and caused a reduction in TGF-ß1 and an increase in SIRT1 in ovary-intact rats. Moreover, CR prevented total antioxidant capacity (TAC) decrease and malondialdehyde (MDA) increase resulting from AKI. Before AKI, an increase in body weight, fasting blood sugar (FBS), low-density lipoprotein (LDL), triglyceride (TG), and total cholesterol (TC), and a decrease in high-density lipoprotein (HDL) were observed in OVX rats compared to sham rats, but CR prevented these changes. The effects of TR were similar to those of CR in all indicators except for TGF-ß1, SIRT1, urea, creatinine, and albumin. CONCLUSION: The present study indicated that CR is more effective than TR in preventing AKI, probably by increasing SIRT1 and decreasing TGF-ß1 in ovary-intact animals.

Extracellular vesicles from apoptotic BMSCs ameliorate osteoporosis via transporting regenerative signals.

Rationale: Mesenchymal stromal cells (MSCs) are considered a promising resource for cell therapy, exhibiting efficacy in ameliorating diverse bone diseases. However, most MSCs undergo apoptosis shortly after transplantation and produce apoptotic extracellular vesicles (ApoEVs). This study aims to clarify the potential role of ApoEVs from apoptotic MSCs in ameliorating osteoporosis and molecular mechanism. Methods: In this study, Dio-labeled bone marrow mesenchymal stem cells (BMSCs) were injected into mice to track BMSCs apoptosis and ApoEVs production. ApoEVs were isolated from BMSCs after inducing apoptosis, the morphology, size distribution, marker proteins expression of ApoEVs were characterized. Protein mass spectrometry analysis revealed functional differences in proteins between ApoEVs and BMSCs. BMSCs were adopted to test the cellular response to ApoEVs. Ovariectomy mice were used to further compare the ability of ApoEVs in promoting bone formation. SiRNA and lentivirus were used for gain and loss-of-function assay. Results: The results showed that BMSCs underwent apoptosis within 2 days after being injected into mice and produce a substantial quantity of ApoEVs. Proteomic analysis revealed that ApoEVs carried a diverse functional array of proteins, and easily traversed the circulation to reach the bone. After being phagocytized by endogenous BMSCs, ApoEVs efficiently promoted the proliferation, migration, and osteogenic differentiation of BMSCs. In an osteoporosis mouse model, treatment of ApoEVs alleviated bone loss and promoted bone formation. Mechanistically, ApoEVs carried Ras protein and activated the Ras/Raf1/Mek/Erk pathway to promote osteogenesis and bone formation in vitro and in vivo. Conclusion: Given that BMSC-derived ApoEVs are high-yield and easily obtained, our data underscore the substantive role of ApoEVs from dying BMSCs to treat bone loss, presenting broad implications for cell-free therapeutic modalities.

Estrogen deprivation and estrogen receptor α antagonism decrease DSS colitis in female mice.

The association of hormonal contraception with increased risk of inflammatory bowel disease (IBD) observed in females suggests involvement of ovarian hormones, such as estradiol, and the estrogen receptors in the progression of intestinal inflammation. Here, we investigated the effects of prophylactic SERM2 and estradiol supplementation in dextran sulfate sodium-induced colitis using mice with intact ovaries and ovariectomized (OVX) female mice. We found that graded colitis score was threefold reduced in the OVX mice, compared to mice with intact ovaries. Estradiol supplementation, however, aggravated the colitis in OVX mice, increasing the colitis score to a similar level than what was observed in the intact mice. Further, we observed that immune infiltration and gene expression of inflammatory interleukins Il1b, Il6, and Il17a were up to 200-fold increased in estradiol supplemented OVX colitis mice, while a mild but consistent decrease was observed by SERM2 treatment in intact animals. Additionally, cyclo-oxygenase 2 induction was increased in the colon of colitis mice, in correlation with increased serum estradiol levels. Measured antagonist properties of SERM2, together with the other results presented here, indicates an exaggerating role of ERα signaling in colitis. Our results contribute to the knowledge of ovarian hormone effects in colitis and encourage further research on the potential use of ER antagonists in the colon, in order to alleviate inflammation.

Photobiomodulation and mesenchymal stem cell-conditioned medium for the repair of experimental critical-size defects.

Orthopedic surgeons face a significant challenge in treating critical-size femoral defects (CSFD) caused by osteoporosis (OP), trauma, infection, or bone tumor resections. In this study for the first time, the application of photobiomodulation (PBM) and bone marrow mesenchymal stem cell-conditioned medium (BM-MSC-CM) to improve the osteogenic characteristics of mineralized bone scaffold (MBS) in ovariectomy-induced osteoporotic (OVX) rats with a CSFD was tested. Five groups of OVX rats with CSFD were created: (1) Control (C); (2) MBS; (3) MBS + CM; (4) MBS + PBM; (5) MBS + CM + PBM. Computed tomography scans (CT scans), compression indentation tests, and histological and stereological analyses were carried out after euthanasia at 12 weeks following implantation surgery. The CT scan results showed that CSFD in the MBS + CM, MBS + PBM, and MBS + CM + PBM groups was significantly smaller compared to the control group (p = 0.01, p = 0.04, and p = 0.000, respectively). Moreover, the CSFD size was substantially smaller in the MBS + CM + PBM treatment group than in the MBS, MBS + CM, and MBS + PBM treatment groups (p = 0.004, p = 0.04, and p = 0.01, respectively). The MBS + PBM and MBS + CM + PBM treatments had significantly increased maximum force relative to the control group (p = 0.01 and p = 0.03, respectively). Bending stiffness significantly increased in MBS (p = 0.006), MBS + CM, MBS + PBM, and MBS + CM + PBM treatments (all p = 0.004) relative to the control group. All treatment groups had considerably higher new trabecular bone volume (NTBV) than the control group (all, p = 0.004). Combined therapies with MBS + PBM and MBS + CM + PBM substantially increased the NTBV relative to the MBS group (all, p = 0.004). The MBS + CM + PBM treatment had a markedly higher NTBV than the MBS + PBM (p = 0.006) and MBS + CM (p = 0.004) treatments. MBS + CM + PBM, MBS + PBM, and MBS + CM treatments significantly accelerated bone regeneration of CSFD in OVX rats. PBM + CM enhanced the osteogenesis of the MBS compared to other treatment groups.

Parathyroid hormone (1-34) retards the lumbar facet joint degeneration and activates Wnt/ß-catenin signaling pathway in ovariectomized rats.

PURPOSE: Facet joint degeneration (FJD) is a major cause of low back pain. Parathyroid hormone (PTH) (1-34) is commonly used to treat osteoporosis. However, little is known about its effects on FJD induced by estrogen deficiency. This study aims to investigate the effects of PTH (1-34) on FJD induced by estrogen deficiency and the underlying pathogenesis of the disease. METHODS: Forty 3-month-old female Sprague-Dawley rats were randomly divided into four groups: 30 received bilateral ovariectomy (OVX) followed by 12 weeks of treatment with normal saline, PTH (1-34) or 17ß-estradiol (E2), and 10 received sham surgery followed by administration of normal saline. Status and Wnt/ß-catenin signaling activity in the cartilage and subchondral bone of the L4-L5 FJs and serum biomarkers were analyzed. RESULTS: Administration of PTH (1-34) and E2 ameliorated cartilage lesions, and significantly decreased MMP-13 and caspase-3 levels and chondrocyte apoptosis. PTH (1-34) but not E2 significantly increased cartilage thickness, number of chondrocytes, and the expression of aggrecan. PTH (1-34) significantly improved microarchitecture parameters of subchondral bone, increased the expression of collagen I and osteocalcin, and decreased RANKL/OPG ratio. E2 treatment significantly increased the OPG level and decreased the RANKL/OPG ratio in the subchondral bone of ovariectomized rats, but it did not significantly improve the microarchitecture parameters of subchondral bone. Wnt3a and ß-catenin expression was significantly reduced in the articular cartilage and subchondral bone in OVX rats, but PTH (1-34) could increase the expression of these proteins. E2 significantly increased the activity of Wnt/ß-catenin pathway only in cartilage, but not in subchondral bone. The restoration of Wnt/ß-catenin signaling had an obvious correlation with the improvement of some parameters associated with the FJs status. CONCLUSION: Wnt/ß-catenin signaling may be a potential therapeutic target for FJD induced by estrogen deficiency. PTH (1-34) is effective in treating this disease with better efficacy than 17ß-estradiol, and the efficacy may be attributed to its restoration of Wnt/ß-catenin signaling.

Repositioning of baricitinib for management of memory impairment in ovariectomized/D-galactose treated rats: A potential role of JAK2/STAT3-PI3K/AKT/mTOR signaling pathway.

AIMS: Neuroinflammation plays a pivotal role in amyloid ß (Aß) plaques formation which is among the hallmarks of Alzheimer's disease (AD). The present study investigated the potential therapeutic effects of baricitinib (BAR), a selective JAK2/ STAT3 inhibitor, in ovariectomized/ D-galactose (OVX/D-gal) treated rats as a model for AD. MAIN METHODS: To induce AD, adult female rats (130-180 g) underwent bilateral ovariectomy and were injected daily with 150 mg/kg, i.p. D-gal for 8 consecutive weeks. BAR (10 and 50 mg/kg/day) was then given orally for 14 days. KEY FINDINGS: BAR in a dose-dependent effect mitigated OVX/D-gal-induced aberrant activation of JAK2/STAT3 signaling pathway resulting in significant decreases in the expression of p-JAK 2, and p-STAT3 levels, along with deactivating AKT/PI3K/mTOR signaling as evidenced by deceased protein expression of p-AKT, p-PI3K, and p-mTOR. As a result, neuroinflammation was diminished as evidenced by decreased NF-κß, TNF-α, and IL-6 levels. Moreover, oxidative stress biomarkers levels as iNOS, and MDA were reduced, whereas GSH was increased by BAR. BAR administration also succeeded in reverting histopathological alterations caused by OVX/D-gal, increased the number of intact neurons (detected by Nissl stain), and diminished astrocyte hyperactivity assessed as GFAP immunoreactivity. Finally, treatment with BAR diminished the levels of Aß. These changes culminated in enhancing spatial learning and memory in Morris water maze, and novel object recognition test. SIGNIFICANCE: BAR could be an effective therapy against neuroinflammation, astrogliosis and cognitive impairment induced by OVX/ D-gal where inhibiting JAK2/STAT3- AKT/PI3K/mTOR seems to play a crucial role in its beneficial effect.

Attenuating bone loss in osteoporosis: the potential of corylin (CL) as a therapeutic agent.

The global prevalence of osteoporosis is being exacerbated by the increasing number of aging societies and longer life expectancies. In response, numerous drugs have been developed in recent years to mitigate bone resorption and enhance bone density. Nonetheless, the efficacy and safety of these pharmaceutical interventions remain constrained. Corylin (CL), a naturally occurring compound derived from the anti-osteoporosis plant Psoralea corylifolia L., has exhibited promising potential in impeding osteoclast differentiation. This study aims to evaluate the effect and molecular mechanisms of CL regulating osteoclast differentiation in vitro and its potential as a therapeutic agent for osteoporosis treatment in vivo. Our investigation revealed that CL effectively inhibits osteoclast formation and their bone resorption capacity by downregulating the transcription factors NFATc1 and c-fos, consequently resulting in the downregulation of genes associated with bone resorption. Furthermore, it has been observed that CL can effectively mitigate the migration and fusion of pre-osteoclast, while also attenuating the activation of mitochondrial mass and function. The results obtained from an in vivo study have demonstrated that CL is capable of attenuating the bone loss induced by ovariectomy (OVX). Based on these significant findings, it is proposed that CL exhibits considerable potential as a novel drug strategy for inhibiting osteoclast differentiation, thereby offering a promising approach for the treatment of osteoporosis.

Dietary Puerarin Translocates to Femur and Suppresses Osteoclast Differentiation in Ovariectomized Mice.

Osteoporosis is characterized by bone loss and deterioration in bone microstructure, leading to bone fragility. It is strongly correlated with menopause in women. Previously, we reported that diets supplemented with a kudzu (Pueraria lobata) vine extract suppressed bone resorption in ovariectomized (OVX) mice, a postmenopausal model. The main isoflavone in kudzu is puerarin (daidzein-8-C-glycoside). Puerarin (daidzein-8-C-glycoside), which is main isoflavone of kudzu, probably contributes to the beneficial effect. However, the underlying mechanism is unclear. Therefore, the nutrikinetics of puerarin and the comparison with the suppressive effects of kudzu isoflavones on osteoclast differentiation was examined in this study. We demonstrated that orally administered puerarin was absorbed from the gut and entered the circulation in an intact form. In addition, puerarin accumulated in RAW264.7 pre-osteoclast cells in a time-dependent manner. Tartrate-resistant acid phosphatase activity was decreased by puerarin treatment in a concentration-dependent manner in RAW264.7 cells stimulated with the receptor activator of nuclear factor kappa-B ligand. Ovariectomy-induced elevated bone resorption was suppressed, and the fragile bone strength was improved by puerarin ingestion in the diet. These findings suggested that orally administered puerarin was localized in bone tissue and suppressed bone resorption and osteoclastogenesis in ovariectomized mice.

Estrogen deficiency induces changes in bone matrix bound water that do not closely correspond with bone turnover.

Postmenopausal osteoporosis, marked by estrogen deficiency, is a major contributor to osteoporotic fractures, yet early prediction of fractures in this population remains challenging. Our goal was to explore the temporal changes in bone-specific inflammation, oxidative stress, bone turnover, and bone-matrix water, and their relationship with estrogen deficiency-induced modifications in bone structure and mechanical properties. Additionally, we sought to determine if emerging clinically translatable imaging techniques could capture early bone modifications prior to standard clinical imaging. Two-month-old female Sprague Dawley rats (n = 48) underwent ovariectomy (OVX, n = 24) or sham operations (n = 24). A subgroup of n = 8 rats per group was sacrificed at 2-, 5-, and 10-weeks post-surgery to assess the temporal relationships of inflammation, oxidative stress, bone turnover, bone matrix water, mechanics, and imaging outcomes. OVX rats exhibited higher body weight compared to sham rats at all time points. By 5-weeks, OVX animals showed elevated markers of inflammation and oxidative stress in cortical bone, which persisted throughout the study, while cortical bone formation rate did not differ from sham until 10-weeks. DXA outcomes did not reveal differences between OVX and sham at any time point. Bound water, assessed using ultrashort echo time magnetic resonance imaging (UTE MRI), was lower in OVX at the earliest time point (2-weeks) and reduced again at 10-weeks with no difference at 5-weeks. These data demonstrate that bound water assessment using novel UTE MRI technology was lower at the earliest time point following OVX. However, no temporal relationship with bone turnover, inflammation, or oxidative stress was observed at the time points assessed in this study. These findings underscore both the increased need to understand bone hydration changes and highlight the usefulness of UTE MRI for non-invasive bone hydration measurements.

Evaluation of the Influence of Hypolipidemic Medication on Albino Wistar Rats' Bone Tissue by NMR Diffusiometry.

Introduction: The ongoing concern of the medical profession regarding chronic medication is related to increasing patient adherence and compliance to treatment and reducing medication side effects. In this respect, drugs represented by fixed-dose combinations of active substances within the same tablet have emerged. Such a principle can be extrapolated by following the potential beneficial effects that a chronic medication can have on chronic pathologies affecting different systems. Materials and Methods: The study included 48 female Albino Wistar rats, aged 16-18 months, which were divided into two groups: ovariectomized and non-ovariectomized rats. One batch of 12 non-ovariectomized rats received no treatment, becoming a control batch (NOVX-M). The ovariectomized (OVX) group was divided into 3 batches of 12 rats each: no treatment, control (OVX-M), fenofibrate-treated (OVX-F) and statin-treated (OVX-S) rats. At 12 weeks after ovariectomy, a femoral fracture occurred in the right hind limb of all animals included in the experiment To reveal the changes, at intervals of 2, 4, 6 and 8 weeks post-fracture, the proximal part of the femur was evaluated by NMR diffusiometry, which allows random motion of proton molecules expressed by self-diffusion coefficients, D, thus allowing analysis of the size and complexity of microscopic order cavities within biological structures, such as pores inside bones. Results: The effects of hypolipidemic medication in the absence of estrogen were evidenced, proving the beneficial effect that fenofibrate can have in preserving healthy tissue exposed to osteoporotic risk during the menopausal period. The effects of lipid-lowering medication are also influenced by the duration of administration. Conclusions: Osteoporosis and heart disease are two chronic pathologies that affect mainly female population in the second half of life, and proving the dual therapeutic potential of lipid-lowering medication may also have positive effects by increasing adherence and compliance to treatment.