Exploring Raloxifene-based Metallodrugs: A Versatile Vector Combined with Pt(II), Palladium(II) and Nickel(II) Dichlorides and Carborates against Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) poses challenges in therapy due to the absence of target expression such as estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). Frequently, the treatment of TNBC involves the combination of several therapeutics. However, an enhanced therapeutic effect can be also achieved within a single molecule. The efficacy of raloxifene can be improved by designing a raloxifene-based hybrid drug bearing a 2,2'-bipyridine moiety (2). Integration of platinum(II), palladium(II), and nickel(II) complexes into this structure dramatically changed the cytotoxicity. The platinum(II) dichloride complex 3 did not demonstrate any activity, while palladium(II) and nickel(II) dichloride complexes 4 and 5 exhibited various cytotoxic behavior towards different types of hormone-receptor positive (HR+) cancer and TNBC cell lines. The replacement of the two chlorido ligands in 3‒5 with a dicarbollide (carborate) ion [C2B9H11]2- resulted in reduced activity of compounds 6, 7, and 8. However, the palladacarborane complex 7 demonstrated higher selectivity towards TNBC. Furthermore, the mechanism of action was shifted from cytotoxic to explicitly cytostatic with detectable proliferation arrest and accelerated aging, characterized by senescence-associated phenotype of TNBC cells. This study provides valuable insights into the development of hybrid therapeutics against TNBC.

Raloxifene increases the risk of gastroesophageal reflux disease, Barrett's esophagus, and esophageal stricture in postmenopausal women with osteoporosis

BACKGROUND AND AIMS

Estrogen-based therapies may increase the risk of gastroesophageal reflux (GERD) and its complications. We aimed to determine the effect of raloxifene on the development of GERD, Barrett's esophagus, and esophageal stricture in postmenopausal women with osteoporosis.

METHODS

This was a population-based, propensity-matched cohort study using the TriNetX platform. Patients 50 years and older with a diagnosis of "menopause" and "osteoporosis" were included in this study. Odds ratios (OR) and 95% confidence intervals (CI) were calculated for new GERD, esophageal stricture and Barrett's esophagus after raloxifene exposure. The control cohort consisted of patients who did not start any hormonal replacement therapy. We conducted a multivariable logistic regression analysis to evaluate the effect of confounding variables and also addressed common confounding medications with 1:1 propensity score-matching. Internal validity was confirmed by comparing to negative controls (lisinopril, atorvastatin) and positive controls (metformin, ibuprofen, aspirin).

RESULTS

Five thousand four hundred and seventy two postmenopausal women with osteoporosis were on raloxifene of which 1908 (34.86%) developed GERD, compared to 296,067 postmenopausal who were not on raloxifene of which 90,643 (30.62%) developed GERD (OR 1.2; 95% CI 1.10-1.31, p < 0.0001). This persisted after adjusting for common medications known to affect GERD. Raloxifene was identified as a risk factor for GERD in a multivariate analysis, controlling for factors including age, obesity, smoking, and alcohol use (OR 1.51, 95% Wald CI 1.47-1.53). Raloxifene was associated with esophageal stricture (OR 1.60; 95% Wald CI 1.51-1.69) and Barrett's esophagus (OR 1.50; 95% Wald CI 1.37-1.63) in multivariate analysis. These associations persisted using sensitivity analyses.

CONCLUSION

Raloxifene increases the risk of GERD, esophageal stricture and Barrett's esophagus in postmenopausal women with osteoporosis. Further studies are needed to confirm our findings.

Comparative Pharmacokinetic Profiles of a Novel Low-Dose Micronized Formulation of Raloxifene 45 mg (AD-101) and the Conventional Raloxifene 60 mg in Healthy Subjects

Raloxifene hydrochloride shows poor bioavailability (only 2%) when orally administered because of its poor aqueous solubility and its extensive first-pass metabolism. A new micronized formulation of raloxifene was developed to improve bioavailability via enhanced gastrointestinal absorption. The primary objective of this study was to evaluate the pharmacokinetic characteristics of a new micronized raloxifene formulation (AD-101) in comparison with the conventional raloxifene formulation. This study was designed as an open-label, randomized, 2-treatment-period, crossover study with a 2-week washout period. Two treatments consisted of micronized raloxifene 45 mg daily; and conventional raloxifene 60 mg daily administered in fasting conditions. Plasma raloxifene concentrations were determined by a validated method using ultra-fast liquid chromatography-tandem mass spectrometry, and pharmacokinetic parameters were calculated using a noncompartmental model. In total, 49 subjects completed the study. The geometric mean ratio (micronized/conventional) of the maximum concentration and the area under the plasma concentration-time curve from time zero to the last concentration values were 1.08 (90% CI, 0.95-1.24) and 0.97 (90% CI, 0.89-1.05), respectively. The adverse event profile did not differ between the 2 formulations. The results demonstrate that micronized formulation of raloxifene 45 mg is equivalent to conventional formulation of raloxifene 60 mg when administered at the single dose in the fasted state. After single oral dosing of AD-101, there were no serious or unexpected adverse events.

The Direct and Long-Term Effects of Raloxifene as Adjunctive Treatment for Schizophrenia-Spectrum Disorders: A Double-Blind, Randomized Clinical Trial

BACKGROUND AND HYPOTHESIS

Several studies suggest that raloxifene, a selective estrogen receptor modulator, improves symptoms and cognition in post-menopausal women with Schizophrenia-Spectrum Disorders (SSD). We aimed to assess the effects of adjunctive raloxifene in women and men with SSD.

STUDY DESIGN

This parallel, randomized, double-blind, placebo-controlled trial included adult SSD patients across the Netherlands and Belgium. Participants were stratified by age, sex, and global functioning and randomly assigned 1:1 to 12-week add-on raloxifene or placebo. Primary outcomes were symptom severity at 6, 12, and 38 weeks and cognition at 12 and 38 weeks, as measured with the Positive and Negative Syndrome Scale and the Brief Assessment of Cognition in Schizophrenia, respectively. Intention-to-treat analyses were performed using linear mixed-effect models.

STUDY RESULTS

We assessed 261 patients for eligibility, of which 102 (28% female) were assigned to raloxifene (n = 52) or placebo (n = 48). Although we found no main effect of raloxifene, secondary sex-specific analysis showed that in women, raloxifene had beneficial effects on negative symptoms at week 6 (LSM -2.92; adjusted P = 0.020) and week 12 (LSM -3.12; adjusted P = 0.030), and on working memory at week 38 (LSM 0.73; adjusted P = 0.040), while having negative effects on working memory at week 38 in men (LSM -0.53; adjusted P = 0.026). The number of adverse events was similar between groups.

CONCLUSIONS

Our results do not support the use of raloxifene in patients with SSD in general, but suggest female-specific beneficial effects of raloxifene on negative symptoms and working memory. Our findings encourage further research on sex-specific pharmacotherapeutic treatment.

Efficacy and safety of medications for osteoporosis in kidney transplant recipients or patients with chronic kidney disease: A meta-analysis

This study conducted a meta-analysis to analyze the efficacy and safety of osteoporosis medications in kidney transplant recipients and patients with chronic kidney disease (CKD). PubMed, Embase, the Cochrane Central Register of Controlled Trials were searched from the date of their inception through October 21, 2022. We performed a meta-analysis of the efficacy and safety of osteoporosis medications in adult patients with stage 3-5 CKD or kidney transplant recipients enrolled in randomized clinical trials (RCTs). We calculated the standard mean deviations with 95% confidence intervals (CI) for bone mineral density (BMD) and T scores after 6 and 12 months treatment, pooled odds ratio and 95% CI for fracture risk, and summarized adverse events. The inclusion criteria were met by 27 studies. Out of this, 19 studies were included for the meta-analysis. In stage 3-4 CKD patients, alendronate increased lumbar spine BMD. In patients at stage 5 CKD and undergoing hemodialysis, alendronate and raloxifene increased lumbar spine BMD. After 6 months, the BMD of kidney transplant recipients was seen to be significantly increased; however, there was no difference after 12 months, and the risk of fracture did not reduce. Thus, there is no evidence that these medications reduce the risk of fracture, and their effect on BMD and fracture remains unproven. These medications may increase the incidence of adverse events and their safety needs to be further evaluated. Therefore, we cannot draw a definitive conclusion about the efficacy and safety of osteoporosis medications in the above group of patients.

The role of PKN1 in glioma pathogenesis and the antiglioma effect of raloxifene targeting PKN1

PKN1 (protein kinase N1), a serine/threonine protein kinase family member, is associated with various cancers. However, the role of PKN1 in gliomas has rarely been studied. We suggest that PKN1 expression in glioma specimens is considerably upregulated and positively correlates with the histopathological grading of gliomas. Knocking down PKN1 expression in glioblastoma (GBM) cells inhibits GBM cell proliferation, invasion and migration and promotes apoptosis. In addition, yes-associated protein (YAP) expression, an essential effector of the Hippo pathway contributing to the oncogenic role of gliomagenesis, was also downregulated. In contrast, PKN1 upregulation enhances the malignant characteristics of GBM cells and simultaneously upregulates YAP expression. Therefore, PKN1 is a promising therapeutic target for gliomas. Raloxifene (Ralo), a commonly used selective oestrogen-receptor modulator to treat osteoporosis in postmenopausal women, was predicted to target PKN1 according to the bioinformatics team from the School of Mathematics, Tianjin Nankai University. We showed that Ralo effectively targets PKN1, inhibits GBM cells proliferation and migration and sensitizes GBM cells to the major chemotherapeutic drug, Temozolomide. Ralo also reverses the effect of PKN1 on YAP activation. Thus, we confirm that PKN1 contributes to the pathogenesis of gliomas and may be a potential target for Ralo adjuvant glioma therapy.

The Interplay of Raloxifene and Sonochemical Bio-Oss in Early Maxillary Sinus Bone Regeneration: A Histological and Immunohistochemical Analysis in Rabbits

The study aimed to assess the efficacy of using Raloxifene with ultrasonic processing to enhance Bio-Oss®, a bone graft substitute, for maxillary sinus bone height reconstruction. A total of 24 rabbit maxillary sinuses were distributed into three groups, each receiving different treatments: Bio-Oss® only, sonicated Bio-Oss, and sonicated Bio-Oss® with Raloxifene. Surgical procedures and subsequent histomorphometric and immunohistochemistry analyses were conducted to evaluate the bone formation, connective tissue, and remaining biomaterial, as well as the osteoblastic differentiation and maturation of collagen fibers. Results indicated that the sonicated Bio-Oss® and Bio-Oss® groups showed similar histological behavior and bone formation, but the Raloxifene group displayed inflammatory infiltrate, low bone formation, and disorganized connective tissue. The statistical analysis confirmed significant differences between the groups in terms of bone formation, connective tissue, and remaining biomaterial. In conclusion, the study found that while sonicated Bio-Oss® performed comparably to Bio-Oss® alone, the addition of Raloxifene led to an unexpected delay in bone repair. The findings stress the importance of histological evaluation for accurate bone repair assessment and the necessity for further investigation into the local application of Raloxifene. Future research may focus on optimizing bone substitutes with growth factors to improve bone repair.

Raloxifene, a SERM targets PD-L1: an in-silico study

OBJECTIVES

Immunotherapeutic interventions in cancer have been considerably successful and widely accepted for cancer treatment, but are costly and cannot be afforded by all patients. Because of the high cost, the pharmaceutical research groups across the world are sufficiently motivated to discover or design small molecule inhibitors to treat cancer through inhibition of the immune checkpoint proteins previously targeted with monoclonal antibodies. The presented study was designed with an aim to establish raloxifene, a selective estrogen receptor modulator (SERM) as a potential ligand of the immune checkpoint protein Programmed death ligand-1 (PD-L1).

METHODS

In the presented study, the in-silico approach was used for identifying a lead molecule against PD-L1. The hits were screened using the similarity-search method, and drug-likeliness analysis, and the leads were identified through ligand-docking using Autodock. In-vitro cytotoxicity analysis was carried out using the standard sulphorhodamine B (SRB) assay and the wound healing analysis to show the inhibition of cellular migration was performed using the standard scratch assay.

RESULTS

The in-silico study revealed that raloxifene showed a high drug likelihood and higher binding affinity with PD-L1 as compared to the positive control (BMS-1166; BMS is Bristol Myers Squibb). The binding of raloxifene was shown to occur in the same region as the FDA-approved monoclonal antibodies atezolizumab and durvalumab, indicating the potential of raloxifene for PD1/PD-L1 blockade. In the in-vitro studies, raloxifene showed a time-dependent reduction in IC50 values for the cell line HCT116 (colon cancer). The scratch assay also revealed that raloxifene significantly reduced the migratory potential of HCT-116 cells in-vitro.

CONCLUSIONS

PD-L1 is a potential target of the SERM raloxifene in-silico. Overall, this study is one step further towards immune checkpoint blockade using small-molecule inhibitors.

Neuroprotective Potential of Raloxifene via G-Protein-Coupled Estrogen Receptors in Aβ-Oligomer-Induced Neuronal Injury

Amyloid-β (Aβ) is one of the causes of Alzheimer's disease (AD), damaging nerve membranes and inducing neurotoxicity. AD is more prevalent in female patients than in male patients, and women are more susceptible to developing AD due to the decline in estrogen levels around menopause. Raloxifene, a selective estrogen receptor modulator, exhibits protective effects by activating the transmembrane G-protein-coupled estrogen receptor (GPER). Additionally, raloxifene prevents mild cognitive impairment and restores cognition. However, the influence of raloxifene via GPER on highly toxic Aβ-oligomers (Aβo)-induced neurotoxicity remains uncertain. In this study, we investigated the GPER-mediated neuroprotective effects of raloxifene against the neurotoxicity caused by Aβo-induced cytotoxicity. The impact of raloxifene on Aβo-induced cell damage was evaluated using measures such as cell viability, production of reactive oxygen species (ROS) and mitochondrial ROS, peroxidation of cell-membrane phospholipids, and changes in intracellular calcium ion concentration ([Ca2+]i) levels. Raloxifene hindered Aβo-induced oxidative stress and reduced excessive [Ca2+]i, resulting in improved cell viability. Furthermore, these effects of raloxifene were inhibited with pretreatment with a GPER antagonist. Our findings suggest that raloxifene safeguards against Aβo-induced neurotoxicity by modifying oxidative parameters and maintaining [Ca2+]i homeostasis. Raloxifene may prove effective in preventing and inhibiting the progression of AD.

Hemostatic Effects of Raloxifene in Ovariectomized Rats

This study aimed to explore the effects of raloxifene (Rx) and estradiol (E₂) on prothrombin time (PT), partial thromboplastin time (APTT), coagulation factors (VII, X, XI), and fibrinogen concentrations in rats. Female rats were ovariectomized 11 days prior to starting the treatment. Afterward, they received Rx or E₂ (1, 10, 100, and 1000 µg/kg) or propylene glycol (0.3 mL; vehicle, V) subcutaneously for 3 consecutive days. Plasma was collected to measure the hemostatic parameters. Rx significantly increased PT (8%, at 1000 µg/kg; p < 0.05) and APTT at all doses evaluated (32, 70, 67, 30%; p < 0.05, respectively). Rx (1, 10, 100, and 1000 µg/kg) decreased the activity of factor VII by -20, -40, -37, and -17% (p < 0.05), respectively, and E₂ increased it by 9, 34, 52, and 29%. Rx reduced factor X activity at 10 and 100 µg/kg doses (-30, and -30% p < 0.05), and E₂ showed an increment of 24% with 1000 µg/kg dose only. Additionally, Rx (1, 10, 100 µg/kg) diminished FXI activity (-71, -62, -66; p < 0.05), E₂ (1 and 10 µg/kg) in -60 and -38, respectively (p < 0.05), and Rx (1000 µg/kg) produced an increment of 29% (p < 0.05) in fibrinogen concentration, but not E₂. Our findings suggest that raloxifene has a protective effect on hemostasis in rats.

Simultaneous estimation of raloxifene and cladrin by HPLC: application to metabolic stability studies in different species

Aim: A reliable, sensitive, HPLC method was developed and validated to simultaneously quantify raloxifene (RLX) and cladrin (CLD). Method: The C18 column was used to analyze RLX and CLD at λ_max 285 and 249 nm. The mobile phase was composed of acetonitrile and 35:65% v/v aqueous solution of 0.1% formic acid. Results: The method was linear over the linearity range of 0.078-20 μg/ml, and the limit of detection and limit of quantification for RLX and CLD were 0.191 and 0.228 and 0.581 and 0.69 μg/ml, respectively. Conclusion: In accordance with the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines, the developed method is precise and accurate for simultaneous estimation of RLX and CLD with applications in in vitro liver microsomal stability in mice, rabbits, dogs, monkeys and humans.

Estradiol and raloxifene as adjunctive treatment for women with schizophrenia: A meta-analysis of randomized, double-blind, placebo-controlled trials

OBJECTIVES

We conducted a comprehensive meta-analysis of all available trials to evaluate the efficacy and safety of estrogen and selective estrogen receptor modulators as adjunctive treatment for women with schizophrenia.

METHODS

Multiple databases were searched from the inception until March 2022. Only randomized, double-blind, placebo-controlled studies (randomized controlled trials) were included. Mean differences (MDs) and their 95% confidence intervals (CIs) were calculated using random effects models.

RESULTS

The meta-analysis included six estradiol versus placebo studies (n = 724) and seven raloxifene versus placebo studies (n = 419), covering a total of 1143 patients. Adjunctive estradiol outperformed the placebo in terms of the Positive and Negative Syndrome Scale (PANSS) total score (MD = -7.29; 95% CI = -10.67 to -3.91; I²  = 59.1%; p < 0.001; k = 9; N = 858), positive symptom score (MD = -1.54; 95% CI = -3.04 to -0.72; I²  = 45.8%; p < 0.001; k = 7; N = 624), negative symptom score (MD = -1.9; 95% CI = -1.77 to -0.34; I²  = 37.6%; p < 0.05; k = 14; N = 1042), and general psychopathology score (MD = -4.27; 95% CI = -7.14 to -1.41; I²  = 76.3%; p < 0.005; k = 7; N = 624). Adjunctive raloxifene outperformed the placebo in terms of the PANSS total score (MD = -6.83; 95% CI = -11.69 to -1.97; I²  = 67.8%; p = 0.006; k = 8; N = 432) and general psychopathology score (MD = -3.82; 95% CI = -6.36 to -1.28; I²  = 65.3%; p < 0.005; k = 8; N = 432).

CONCLUSIONS

Our meta-analysis showed that estradiol and raloxifene are effective and safe adjunctive treatments that improve schizophrenia symptoms in women. Moreover, the effects of estradiol and raloxifene differed in terms of timing and dosage. Both are promising adjunctive treatments that merit further study.

Efficacy of Raloxifene as Add-on Therapy on Disease Activity of Postmenopausal Women with Rheumatoid Arthritis: A Double-blind, Randomized, Placebo-controlled Clinical Trial

OBJECTIVE

The current study aimed to evaluate the effect of raloxifene on the disease activity of postmenopausal patients with rheumatoid arthritis (RA) and the prevention of glucocorticoid- induced osteoporosis.

METHODS

This double-blind, randomized clinical trial was conducted at the Rheumatic Diseases Research Center affiliated with Mashhad University of Medical Sciences from 2015 to 2016. Postmenopausal women with RA were randomly treated with raloxifene or placebo after discontinuation of alendronate. Disease activity was evaluated using DAS28ESR, HAQ, and VAS before and every two months after the intervention. In addition, bone mineral densitometry was performed for patients before and 14 months after the intervention. The disease activity and densitometric criteria were compared between the two groups at a significant level of p <0.05.

RESULTS

A total of 17 patients were allocated to each group. The two groups were similar at baseline in underlying disease, age, duration of RA, duration of alendronate use, laboratory findings, and rheumatoid arthritis drugs. Moreover, the mean scores of DAS28ESR, HAQ, and VAS during visits were not significantly different between the intervention and control groups (p >0.05).

CONCLUSION

The current study results could not prove any clinical benefits of adding raloxifene to standard therapies for patients with rheumatoid arthritis in improving their disease activity compared to placebo.

CLINICAL TRIAL REGISTRATION NUMBER

Trial registration number is NCT02982083.

Targeting Interleukin-6/Glycoprotein-130 Signaling by Raloxifene or SC144 Enhances Paclitaxel Efficacy in Pancreatic Cancer

Interleukine-6 plays a key role in the progression and poor survival in pancreatic ductal adenocarcinoma (PDAC). The present study aimed to clarify if targeting the interleukin-6/glycoprotein-130 signaling cascade using the small-molecule gp130 inhibitor SC144 or raloxifene, a non-steroidal selective estrogen receptor modulator, enhances paclitaxel efficacy. MTT/BrdU assays or TUNEL staining were performed to investigate cell viability, proliferation and apoptosis induction in L3.6pl and AsPC-1 human pancreatic cell lines. In vivo, effects were studied in an orthotopic PDAC mouse model. Tumor specimens were analyzed by qPCR, immunohistochemistry and ELISA. Combination of paclitaxel/raloxifene, but not paclitaxel/SC144, enhanced proliferation and viability inhibition and increased apoptosis compared to single treatment in vitro. Synergy score calculations confirmed an additive influence of raloxifene on paclitaxel. In the PDAC mouse model, both combinations of raloxifene/paclitaxel and SC144/paclitaxel reduced tumor weight and volume compared to single-agent therapy or control. Raloxifene/paclitaxel treatment decreased survivin mRNA expression and showed tendencies of increased caspase-3 staining in primary tumors. SC144/paclitaxel reduced interleukin-6 levels in mice's tumors and plasma. In conclusion, raloxifene or SC144 can enhance the anti-tumorigenic effects of paclitaxel, suggesting that paclitaxel doses might also be reduced in combined chemotherapy to lessen paclitaxel side effects.

Vitamin D Receptor Gene Polymorphisms Affect Osteoporosis-Related Traits and Response to Antiresorptive Therapy

The present study analyzed the effect of vitamin D receptor (VDR) gene polymorphisms (ApaI, TaqI, BsmI, FokI, and Cdx2) on bone mineral density (BMD), biochemical parameters and bone turnover markers, fracture prevalence, and response to three types of antiresorptive therapy (estrogen-progesterone, raloxifene, and ibandronate) in 356 postmenopausal women from Slovakia. Association analysis revealed a significant effect of BsmI polymorphism on lumbar spine BMD, serum osteocalcin (OC), and β-CrossLaps levels. While ApaI and Cdx2 polymorphisms were associated with OC and alkaline phosphatase, TaqI polymorphism affected all turnover markers. ApaI, TaqI, and BsmI genotypes increased the risk of spinal, radial, or total fractures with odds ratios ranging from 2.03 to 3.17. Each of therapy types evaluated had a beneficial effect on all osteoporosis-related traits; however, the VDR gene affected only ibandronate and raloxifene treatment. ApaI/aa, TaqI/TT, and BsmI/bb genotypes showed a weaker or no response to ibandronate therapy in femoral and spinal BMD. The impact of aforementioned polymorphisms on turnover markers was also genotype dependent. On the contrary, only TaqI and BsmI polymorphisms influenced raloxifene therapy, even only in lumbar spine BMD. These results point to the potential of using the VDR gene in personalized pharmacotherapy of osteoporosis.

Computational approach in searching for dual action multitarget inhibitors for osteosarcoma

Osteosarcoma is a common primary malignant bone tumor that typically manifests in the second decade of life. This study aimed to identify osteogenic compounds that potentially serve as multitarget inhibitors for osteosarcoma. The study was a molecular docking study of nine Food and Drug Administration-approved compounds with osteogenic properties to the key membrane proteins of osteosarcoma. The ligands used were raloxifene, simvastatin, dexamethasone, risedronate, ibandronate, zoledronic acid, ascorbic acid, alendronate, and β-glycerophosphate, whereas the target proteins used were RET, fibroblast growth factor receptor 1, KIT, PDGFRA, VEGFR1, and VEGFR2. Chem3D version 15.0.0.106 was used for ligand preparation, and AutoDockTools version 1.5.6 was used for protein preparation, whereas molecular docking was conducted using AutoDock Vina. Raloxifene, simvastatin, and dexamethasone had the lowest binding activity to the target proteins. The binding affinity of raloxifene was from -8.4 to -10.0 kcal mol-1, that of simvastatin was -8.3 to -9.2 kcal mol-1, whereas dexamethasone ranged from -6.9 to -9.1 kcal mol-1. Most types of interactions were hydrophobically followed by hydrogen bonding. The current study suggests that raloxifene, simvastatin, and dexamethasone have the potential to act as multitarget inhibitors for osteosarcoma with the ability to induce bone remodeling.

Human serum albumin-based nanoparticles alter raloxifene administration and improve bioavailability

Osteoporosis is a disease that reduces bone mass and microarchitecture, which makes bones fragile. Postmenopausal osteoporosis occurs due to estrogen deficiency. Raloxifene is a selective estrogen receptor modulator used to treat postmenopausal osteoporosis. However, it has a low bioavailability, which requires long-term, high-dose raloxifene administration to be effective and causes several side effects. Herein, raloxifene was encapsulated in human serum albumin (HSA)-based nanoparticles (Ral/HSA/PSS NPs) as an intravenous-injection pharmaceutical formulation to increase its bioavailability and reduce the treatment dosage and time. In vitro results indicated that raloxifene molecules were well distributed in HSA-based nanoparticles as an amorphous state, and the resulting raloxifene formulation was stabile during long-term storage duration. The Ral/HSA/PSS NPs were both biocompatible and hemocompatible with a decreased cytotoxicity of high-dose raloxifene. Moreover, the intravenous administration of the prepared Ral/HSA/PSS NPs to rats improved raloxifene bioavailability and improved its half-life in plasma. These raloxifene-loaded nanoparticles may be a potential nanomedicine candidate for treating postmenopausal osteoporosis with lower raloxifene dosages.

Mitophagy Induction and Aryl Hydrocarbon Receptor-Mediated Redox Signaling Contribute to the Suppression of Breast Cancer Cell Growth by Taloxifene via Regulation of Inflammasomes Activation

Aims: Raloxifene, a selective estrogen receptor (ER) modulator, has been reported to exert the tumor-suppressive effects in both ER-positive and ER-negative cancer cells; however, the mechanisms underlying its ER-independent anti-cancer effects are poorly understood. The NLRP3 inflammasome, a critical component of the innate immune system, has recently received growing attention owing to its multifaceted roles in various aspects of cancer development. The present study aimed at examining the involvement of NLRP3 inflammasomes in the anti-breast cancer effects of raloxifene and its underlying mechanisms. Results: Raloxifene significantly inhibited the activation of NLRP3 inflammasomes in various breast cancer cell lines. Importantly, forced expression of a gain-of-function variant of NLRP3 rescued breast cancer cells from growth arrest by raloxifene, suggesting that the suppression of NLRP3 inflammasomes activation mediates the raloxifene-induced inhibition of breast cancer growth. Mechanistically, raloxifene suppressed NLRP3 inflammasomes activation by lowering the cellular levels of reactive oxygen species (ROS) through the modulation of redox signaling mediated via aryl hydrocarbon receptor (AhR)-nuclear factor erythroid 2-related factor 2 (Nrf2)-heme oxygenase-1 (HO-1) axis or the impaired generation of mitochondrial ROS in a mitophagy-dependent manner. Further, the blockage of AhR signaling or inhibition of mitophagy abolished the tumor-suppressive effect of raloxifene in a human breast tumor xenograft model. Innovation: We elucidate a novel molecular mechanism underlying the breast tumor suppressing effect of raloxifene. Conclusion: The results observed in this study suggest that the modulation of NLRP3 inflammasomes activation is a critical event in the inhibition of breast tumor growth by raloxifene. Antioxid. Redox Signal. 37, 1030-1050.

Association of raloxifene and tamoxifen therapy with cognitive performance, odds of mild cognitive impairment, and brain MRI markers of neurodegeneration

The aim of this cross-sectional study was to examine whether a history of selective estrogen receptor modifiers (SERMs), tamoxifen and raloxifene, use was associated with cognitive performance, odds of mild cognitive impairment (MCI), or magnetic resonance imaging (MRI) markers of neurodegeneration associated with Alzheimer's disease. We included women with prior history of breast cancer or no prior history of any cancer at enrollment in the Mayo Clinic Study of Aging (MCSA). This information was abstracted using the Rochester Epidemiology Project medical-linkage system. Logistic regression was used to examine associations of SERMs with odds of MCI. Linear regression models were used to examine associations of SERMs with cognitive z-scores (Memory, Executive Function, Language, Visuospatial Skills, Global Cognition), and MRI markers. Among 2840 women aged 50 and older in the MCSA, 151 had a history of breast cancer, and 42 (28%) of these had a history of tamoxifen treatment. A total of 2235 women had no prior history of any cancer, and 76 (3%) of these had a history of raloxifene use. No significant associations between tamoxifen use and cognition, or odds of MCI were observed among women with a history of breast cancer after adjusting for confounders. Similarly, raloxifene use was not significantly associated with cognition, or odds of MCI in women without a history of cancer after adjusting for confounders. We did not find significant associations between the use of either SERM and MRI markers. Use of tamoxifen or raloxifene was not significantly associated with cognition in postmenopausal women.

Nanostructured Lipid Carrier-Based Codelivery of Raloxifene and Naringin: Formulation, Optimization, In Vitro, Ex Vivo, In Vivo Assessment, and Acute Toxicity Studies

This work aimed to develop dual drug-loaded nanostructured lipid carriers of raloxifene and naringin (RLX/NRG NLCs) for breast cancer. RLX/NRG NLCs were prepared using Compritol 888 ATO and oleic acid using a hot homogenization-sonication method and optimized using central composite design (CCD). The optimized RLX/NRG NLCs were characterized and evaluated using multiple technological means. The optimized RLX/NRG NLCs exhibited a particle size of 137.12 nm, polydispersity index (PDI) of 0.266, zeta potential (ZP) of 25.9 mV, and entrapment efficiency (EE) of 91.05% (raloxifene) and 85.07% (naringin), respectively. In vitro release (81 ± 2.2% from RLX/NRG NLCs and 31 ± 1.9% from the RLX/NRG suspension for RLX and 93 ± 1.5% from RLX/NRG NLCs and 38 ± 2.01% from the RLX/NRG suspension for NRG within 24 h). Concurrently, an ex vivo permeation study exhibited nearly 2.3 and 2.1-fold improvement in the permeability profiles of RLX and NRG from RLX/NRG NLCs vis-à-vis the RLX/NRG suspension. The depth of permeation was proved with CLSM images which revealed significant permeation of the drug from the RLX/NRG NLCs formulation, 3.5-fold across the intestine, as compared with the RLX/NRG suspension. An in vitro DPPH antioxidant study displayed a better antioxidant potential of RLX/NRG in comparison to RLX and NRG alone due to the synergistic antioxidant effect of RLX and NRG. An acute toxicity study in Wistar rats showed the safety profile of the prepared nanoformulations and their excipients. Our findings shed new light on how poorly soluble and poorly permeable medicines can be codelivered using NLCs in an oral nanoformulation to improve their medicinal performance.

Comparative Adverse Kidney Outcomes in Women Receiving Raloxifene and Denosumab in a Real-World Setting

Both osteoporosis and kidney diseases are common and intercorrelate to increase morbidity and mortality in elderly women. This study aimed to compare adverse kidney outcome between women initiated with denosumab and a matched group of raloxifene initiators using propensity score matching methods in a large healthcare delivery system in Taiwan. The risks of adverse kidney outcomes were estimated using Cox proportional hazard regression and the change in kidney function over time was analyzed using the linear mixed model. A total of 9444 (4722 in each group) women were identified who matched the inclusion criteria between January 2003 and December, 2018. Denosumab use was significantly associated with higher risk of eGFR decline ≥ 30% from baseline than raloxifene use (aHR: 1.26; 95% CI: 1.16−1.36, p < 0.0001). The mean change in eGFR over time was 1.24 mL/min/1.73 m2 per year in the denosumab group and 0.45 mL/min/1.73 m2 per year in the raloxifene group (p = 0.0004). However, the risks of acute kidney injury (10.53%) and chronic dialysis (0.66%) in this study cohort were not significantly different for the two anti-osteoporosis treatments. Close monitoring of the residual kidney function and treatment effect is needed in those with denosumab.

Risk of developing spontaneous MRONJ in fibrous dysplasia patients treated with bisphosphonates: a systematic review of the literature

OBJECTIVE

The objective of this systematic review was to evaluate the risks of medication-related osteonecrosis of the jaw (MRONJ) in fibrous dysplasia (FD) and McCune-Albright syndrome (MAS) patients treated with bisphosphonates.

METHOD AND MATERIALS

A systematic review of the literature was performed by searching PubMed and Embase databases using MeSH terms (fibrous dysplasia of bone, "fibrous dysplasia, polyostotic," osteonecrosis, jaw, therapeutics, diphosphonates, denosumab, teriparatide, estrogens, hormones, raloxifene hydrochloride, calcitonin, cathepsin K) and non-MeSH terms (antiresorptive therapy, antiresorptives, bisphosphonate, estrogen therapy, hormone therapy, bazedoxifene, cathepsin K inhibitor). Articles were limited to human studies, in English language, in which patients were on antiresorptives for at least 1 year. PRISMA statement guidelines were used to eliminate non-relevant studies. The PICOT question asked was, "Does exposure to bisphosphonates and other antiresorptives cause occurrence of MRONJ in fibrous dysplasia and fibrous dysplasia/McCune-Albright syndrome patients followed up for at least 1 year?"

RESULTS

Eight eligible articles were included in the quantitative synthesis after articles were screened using a PRISMA flowchart. There were 12 reported occurrences of MRONJ among a combined total of 312 fibrous dysplasia and fibrous dysplasia/McCune-Albright syndrome patients (3.85%).

CONCLUSION

Patients with fibrous dysplasia or fibrous dysplasia/McCune-Albright syndrome have a low incidence of MRONJ and may apparently have low susceptibility to spontaneous development of MRONJ.

Bazedoxifene, a Postmenopausal Drug, Acts as an Antimalarial and Inhibits Hemozoin Formation

Despite a remarkable improvement in health care and continued drug discovery efforts, malaria control efforts are continuously challenged by the emergence of drug-resistant parasite strains. Given a long and risky development path of new drugs, repurposing existing drugs for the treatment of malaria is an attractive and shorter path. Tamoxifen, a selective estrogen receptor modulator (SERM) for the treatment and prevention of estrogen receptor-positive breast cancer, possesses antibacterial, antifungal, and antiparasitic activities. Hence, we assessed tamoxifen, raloxifene, and bazedoxifene, which represent the first-, second-, and third-generation SERMs, respectively, for antimalarial activity. Raloxifene and bazedoxifene inhibited the erythrocytic development of Plasmodium falciparum with submicromolar 50% inhibitory concentration (IC₅₀) values. Among the three, bazedoxifene was the most potent and also decreased P. berghei infection in female mice but not in male mice. However, bazedoxifene similarly inhibited P. falciparum growth in erythrocytes of male and female origin, which highlights the importance of sex-specific host physiology in drug efficacy. Bazedoxifene was most potent on early ring-stage parasites, and about 35% of the treated parasites did not contain hemozoin in the food vacuole. Bazedoxifene-treated parasites had almost 34% less hemozoin content than the control parasites. However, both control and bazedoxifene-treated parasites had similar hemoglobin levels, suggesting that bazedoxifene inhibits hemozoin formation and that toxicity due to accumulation of free heme could be a mechanism of its antimalarial activity. Because bazedoxifene is in clinical use and bazedoxifene-chloroquine combination shows an additive antiparasitic effect, bazedoxifene could be an adjunctive partner of currently used antimalarial regimens.

IMPORTANCE The emergence and spread of drug-resistant strains of the human malaria parasite Plasmodium falciparum has necessitated new drugs. Selective estrogen receptor modulators are in clinical use for the prevention and treatment of breast cancer and postmenopausal osteoporosis. We demonstrate that bazedoxifene, a third-generation selective estrogen receptor modulator, has potent inhibitory activity against both susceptible and drug-resistant strains of Plasmodium falciparum. It also blocked the development of Plasmodium berghei in mice. The inhibitory effect was strongest on the ring stage and resulted in the inhibition of hemozoin formation, which could be the major mechanism of bazedoxifene action. Hemozoin is a nontoxic polymer of heme, which is a by-product of hemoglobin degradation by the malaria parasite during its development within the erythrocyte. Because bazedoxifene is already in clinical use for the treatment of postmenopausal osteoporosis, our findings support repurposing of bazedoxifene as an antimalarial.

Binding of raloxifene to human complement fragment 5a (hC5a): a perspective on cytokine storm and COVID19

Human C5a (hC5a), one of the pro-inflammatory glycoproteins of the complement system is known to undergo production hyperdrive in response to stress and infection. hC5a has been associated with the pathogenesis of many chronic and acute diseases, due to its proven ability in triggering the 'cytokine storm', by binding to its cognate receptor C5aR, expressed in myriad of tissues. Given the pleiotropic downstream function of hC5a, it is logical to consider the hC5a or its precursors as potential drug targets, and thus, we have been rationally pursuing the idea of neutralizing the harmful effect of excessive hC5a, by implementing the repurposing strategies for FDA-approved drugs. Indeed, the proof of principle biophysical studies published recently is encouraging, which strongly supports the potential of this strategy. Considering BSA-carprofen as a reference model system, the current study further explores the inherent conformational plasticity of hC5a and its effect in accommodating more than one drug molecule cooperatively at multiple sites. The data generated by recruiting a battery of experimental and computational biology techniques strongly suggest that hC5a can sequentially accommodate more than one raloxifene molecule with an estimated Ki ∼ 0.5 µM and Ki ∼ 3.58 µM on its surface at non-analogous sites. The study hints at exploration of polypharmacology approach, as a new avenue for discovering synergistic drug molecule pairs, or drug molecules with 'broad-range' binding affinity for targeting the different 'hot spots' on hC5a, as an alternative combination therapy for possible management of the 'cytokine storm'-related inflammatory diseases, like COVID19.Communicated by Ramaswamy H. Sarma.

Pseudo-pheochromocytoma due to obstructive sleep apnea: a case report

SUMMARY

Obstructive sleep apnea (OSA) is a condition of intermittent nocturnal upper airway obstruction. OSA increases sympathetic drive which may result in clinical and biochemical features suggestive of pheochromocytoma. We present the case of a 65-year-old male with a 2.9-cm left adrenal incidentaloma on CT, hypertension, symptoms of headache, anxiety and diaphoresis, and persistently elevated 24-h urine norepinephrine (initially 818 nmol/day (89-470)) and normetanephrine (initially 11.2 µmol/day (0.6-2.7)). He was started on prazosin and underwent left adrenalectomy. Pathology revealed an adrenal corticoadenoma with no evidence of pheochromocytoma. Over the next 2 years, urine norepinephrine and normetanephrine remained significantly elevated with no MIBG avid disease. Years later, he was diagnosed with severe OSA and treated with continuous positive airway pressure. Urine testing done once OSA was well controlled revealed complete normalization of urine norepinephrine and normetanephrine with substantial symptom improvement. It was concluded that the patient never had a pheochromocytoma but rather an adrenal adenoma with biochemistry and symptoms suggestive of pheochromocytoma due to untreated severe OSA. Pseudo-pheochromocytoma is a rare presentation of OSA and should be considered on the differential of elevated urine catecholamines and metanephrines in the right clinical setting.

LEARNING POINTS

Obstructive sleep apnea (OSA) is a common condition among adults. OSA may rarely present as pseudo-pheochromocytoma with symptoms of pallor, palpitations, perspiration, headache, or anxiety. OSA should be considered on the differential of elevated urine catecholamines and metanephrines, especially in patients with negative metaiodobenzylguanidine (MIBG) scan results.

Pharmacokinetic Drug Interaction Between Raloxifene and Cholecalciferol in Healthy Volunteers

Osteoporosis is a common skeletal disorder, often leading to fragility fracture. Combination therapy with raloxifene, a selective estrogen receptor modulator, and cholecalciferol (vitamin D₃) has been proposed to improve the overall efficacy and increase compliance of raloxifene therapy for postmenopausal osteoporosis. To our knowledge, there has been no report of any study on the pharmacokinetic interaction between raloxifene and cholecalciferol. This study aimed to evaluate the possible pharmacokinetic interactions between raloxifene and cholecalciferol in healthy adult male Korean volunteers. Twenty subjects completed this open‐label, randomized, single‐dose, 3‐period, 6‐sequence, crossover phase 1 study with a 14‐day washout period. Serial blood samples were collected from 20 hours before dosing to 96 hours after dosing. The plasma concentrations of raloxifene and cholecalciferol were determined using a validated method for high‐performance liquid chromatography with tandem mass spectrometry. The geometric mean ratios (90%CIs) for area under the plasma concentration–time curve from time 0 to the last quantifiable time point and maximum plasma concentration of raloxifene with or without cholecalciferol were 1.02 (0.87‐1.20) and 0.87 (0.70‐1.08), respectively. For baseline‐corrected cholecalciferol, geometric mean ratios (90%CIs) of area under the plasma concentration–time curve from time 0 to the last quantifiable time point and maximum plasma concentration with or without raloxifene were 1.01 (0.93‐1.09) and 0.99 (0.92‐1.06), respectively. Concurrent treatment with raloxifene and cholecalciferol was generally well tolerated. These results suggest that raloxifene and cholecalciferol have no clinically relevant pharmacokinetic drug‐drug interactions when administered concurrently. All treatments were well tolerated, with no serious adverse events.

Raloxifene Modulates Microglia and Rescues Visual Deficits and Pathology After Impact Traumatic Brain Injury

Mild traumatic brain injury (TBI) involves widespread axonal injury and activation of microglia, which initiates secondary processes that worsen the TBI outcome. The upregulation of cannabinoid type-2 receptors (CB2) when microglia become activated allows CB2-binding drugs to selectively target microglia. CB2 inverse agonists modulate activated microglia by shifting them away from the harmful pro-inflammatory M1 state toward the helpful reparative M2 state and thus can stem secondary injury cascades. We previously found that treatment with the CB2 inverse agonist SMM-189 after mild TBI in mice produced by focal cranial blast rescues visual deficits and the optic nerve axon loss that would otherwise result. We have further shown that raloxifene, which is Food and Drug Administration (FDA)-approved as an estrogen receptor modulator to treat osteoporosis, but also possesses CB2 inverse agonism, yields similar benefit in this TBI model through its modulation of microglia. As many different traumatic events produce TBI in humans, it is widely acknowledged that diverse animal models must be used in evaluating possible therapies. Here we examine the consequences of TBI created by blunt impact to the mouse head for visual function and associated pathologies and assess raloxifene benefit. We found that mice subjected to impact TBI exhibited decreases in contrast sensitivity and the B-wave of the electroretinogram, increases in light aversion and resting pupil diameter, and optic nerve axon loss, which were rescued by daily injection of raloxifene at 5 or 10 mg/ml for 2 weeks. Raloxifene treatment was associated with reduced M1 activation and/or enhanced M2 activation in retina, optic nerve, and optic tract after impact TBI. Our results suggest that the higher raloxifene dose, in particular, may be therapeutic for the optic nerve by enhancing the phagocytosis of axonal debris that would otherwise promote inflammation, thereby salvaging less damaged axons. Our current work, together with our prior studies, shows that microglial activation drives secondary injury processes after both impact and cranial blast TBI and raloxifene mitigates microglial activation and visual system injury in both cases. The results thus provide a strong basis for phase 2 human clinical trials evaluating raloxifene as a TBI therapy.

The Impact of Improving Dermal Permeation on the Efficacy and Targeting of Liposome Nanoparticles as a Potential Treatment for Breast Cancer

Breast cancer is the most frequent malignancy in women. This work focuses on developing deformable liposomes as a potential carrier for breast cancer treatment and studying the impact of improving dermal permeation on the efficacy and targeting of liposomes. Raloxifene (RXF), an oestrogen antagonist, was used as a model drug. Using Box-Behnken design, different formulations of RXF-loaded deformable liposome (RLDL) were prepared using different propylene glycol, phospholipid and cholesterol concentrations. The percentage of entrapment efficiency (Y₁), particle size (Y₂), zeta potential (Y₃) and steady-state flux (Y₄) of the prepared formulations were all evaluated. Y₁ and Y₄ were significantly increased and Y₂ and Y₃ were significantly decreased when the propylene glycol concentration was increased. The optimization was obtained and the optimum formulation was that including phospholipid (1.40% w/w), cholesterol (0.15% w/w) and propylene glycol (10% v/v). The selected optimum formulation displayed a % EE of 78.34 ± 1.04% with a steady-state flux of 4.21 ± 0.02 µg/cm²/h. In order to investigate bioavailability, antitumor effectiveness and permeation, the optimum formulation was selected and included in a carbopol gel. The optimum gel formulation had 2.77 times higher bioavailability and, as a result, considerable antitumor action as compared to oral RXF. In conclusion, optimum RLDL gel may be an effective breast cancer treatment.

Raloxifene Protects Cisplatin-Induced Renal Injury in Mice via Inhibiting Oxidative Stress

Purpose

Cisplatin is one of the most widely used antineoplastic drugs but has limited therapeutic effects due to nephrotoxicity. The aim of this study was to determine the possible renoprotective effect of the antioxidant raloxifene on cisplatin-induced nephrotoxicity in mice.

Materials and Methods

Cisplatin-induced acute renal injury was established in female C57 mice that were treated with saline (normal control) or raloxifene over a 7-day period. The body weight of the mice was recorded. Histopathological examinations of the kidney tissues were performed using H&E, PAS staining and TEM. The histomorphology of liver and other organs was observed by H&E staining. The serum levels of creatinine, blood urea nitrogen (BUN), alanine transaminase (ALT) and glutamic oxalacetic transaminase (AST) were analyzed by specific kits. Superoxide dismutase (SOD) and glutathione (GSH) activity, and the content of malondialdehyde (MDA) in the kidney, liver homogenates and HK-2 cells were measured by WST-8 and thiobarbituric acid colorimetric methods. Moreover, the mitochondrial structures of HK-2 cells were performed using TEM. The viability and proliferation of HK-2 cells were examined by CCK-8 and EdU incorporation assays. The mitochondrial membrane potential was measured by JC-1 fluorescence.

Results

Raloxifene significantly reduced the levels of serum creatinine, urea, ALT and AST in the cisplatin-treated mice, and alleviated cisplatin-induced renal and hepatic tissue injury. Furthermore, raloxifene also increased the activity of GSH and SOD in the renal tissues and HK-2 cells, and reduced MDA levels, thereby limiting oxidative stress in the kidney.

Conclusion

Raloxifene protected against cisplatin-induced nephrotoxicity by activating the antioxidant system, along with alleviating liver damage. It should be considered as a potential adjuvant in cisplatin-based chemotherapeutic protocols.

Molecular and Metabolomic Investigation of Celecoxib Antiproliferative Activity in Mono-and Combination Therapy Against Breast Cancer Cell Models

BACKGROUND

Chronic inflammation plays a crucial role in the initiation, promotion, and invasion of tumors, and thus the antiproliferative effects of numerous anti-inflammatory drugs have been frequently reported in the literature. Upregulation of the pro-inflammatory enzyme cyclooxygenase-2 (COX-2) has been linked to various human cancers, including breast cancer.

OBJECTIVES

This research aims to investigate the antiproliferative activity of different Non-steroidal anti-inflammatory drugs (NSAIDs), including COX-2 selective and non-selective agents, against various breast cancer cell lines and to elucidate possible molecular pathways involved in their activity.

METHODS

The antiproliferative and combined effects of NSAIDs with raloxifene were evaluated by MTT assay. Cell migration was assessed using a wound-healing assay. The mechanism of cell death was determined using the Annexin V-FITC/ propidium iodide staining flow cytometry method. A mass spectrometry-based targeted metabolomics approach was used to profile the metabolomic changes induced in the T47d cells upon drug treatment.

RESULTS

Our results have demonstrated that celecoxib, a potent and selective COX-2 inhibitor, resulted in significant antiproliferative activity against all examined breast cancer cell lines with IC50 values of 95.44, 49.50. and 97.70 μM against MDA-MB-231, T47d, and MCF-7, respectively. Additionally, celecoxib exhibited a synergistic effect against T47d cells combined with raloxifene, a selective estrogen receptor modulator. Interestingly, celecoxib treatment increased cell apoptosis and resulted in substantial inhibition of cancer cell migration. In addition, the metabolomic analysis suggests that celecoxib may have affected metabolites (n = 43) that are involved in several pathways, including the tricarboxylic acid cycle, amino acids metabolism pathways, and energy production pathways in cancer cells.

CONCLUSION

Celecoxib may possess potential therapeutic utility for breast cancer treatment as monotherapy or in combination therapy. The reported metabolic changes taking place upon celecoxib treatment may shed light on possible molecular targets mediating the antiproliferative activity of celecoxib in an independent manner of its COX-2 inhibition.

The Effect of Raloxifene Treatment on Lipid Profile in Elderly Individuals: A Systematic Review and Meta-analysis of Randomized Clinical Trials

PURPOSE

To perform a systematic review and meta-analysis of randomized clinical trials (RCTs) to elucidate the effects of raloxifene on the lipid profile in elderly individuals.

METHODS

A systematic review and meta-analysis of RCTs was performed following the PRISMA statement. Data on triglycerides (TGs), total cholesterol (TC), HDL-C, and LDL-C were extracted. Relevant publications up to October 2020 were detected through searches in the PubMed/MEDLINE, Web of Science, Scopus, and Embase databases. Changes were reported as weighted mean differences (WMDs) and 95% CIs using random-effects models.

FINDINGS

Nine studies were selected, with a duration of intervention ranging from 2 and 12 months and a raloxifene dose of 60 to 120 mg/d. Studies were performed in healthy individuals and in those with disorders, such as osteoporosis, type 2 diabetes, and kidney disease required long-term hemodialysis. Overall, TG (WMD, -6.50 mg/dL; 95% CI, -34.18 to 21.20 mg/eL; P = 0.646), LDL-C (WMD, -17.86 mg/dL; 95% CI, -42.44 to 6.72 mg/dL; P = 0.154), and HDL-C (WMD, 2.35 mg/dL; 95% CI, -1.14 to 5.84 mg/dL; P = 0.187) levels did not change significantly after the administration of raloxifene. In contrast, TC levels decreased after raloxifene therapy (WMD, -6.59 mg/dL; 95% CI, -13.13 to -0.05 mg/dL; P = 0.048).

IMPLICATIONS

Raloxifene therapy decreased TC levels but did not alter TG, HDL-C, and LDL-C concentrations in elderly individuals. Regarding the LDL-C levels, although the finding lacked statistical significance, we believe that there was a mean reduction that deserves further clinical attention as much as TC.

Raloxifene Ameliorates Glucosamine-Induced Insulin Resistance in Ovariectomized Rats

Osteoarthritis (OA) and osteoporosis (OP) are common among older women, especially postmenopausal women. Glucosamine (GlcN) is a common medication for OA, but it may induce insulin resistance and β-cell dysfunction, especially if ovarian hormones are lacking. Raloxifene (RLX) is a selective estrogen receptor modulator and also an OP drug. Previously, we found that estrogen could improve GlcN-induced insulin resistance in ovariectomized (OVX) rats. Here, we further hypothesized that RLX, similarly to estrogen, can ameliorate GlcN-induced insulin resistance in OVX rats. We used GlcN to induce insulin resistance in OVX rats as a model for evaluating the protective effects of RLX in vivo. We used a pancreatic β-cell line, MIN-6, to study the mechanisms underlying the effect of RLX in GlcN-induced β-cell dysfunction in vitro. Increases in fasting plasma glucose, insulin, and homeostasis model assessments of insulin resistance in OVX Sprague Dawley rats treated with GlcN were reversed by RLX treatment (n = 8 in each group). Skeletal muscle GLUT-4 increased, liver PEPCK decreased, pancreatic islet hypertrophy, and β-cell apoptosis in OVX rats treated with GlcN was ameliorated by RLX. The negative effects of GlcN on insulin secretion and cell viability in MIN-6 cells were related to the upregulation of reticulum (ER) stress-associated proteins (C/EBP homologous protein, phospho-extracellular signal-regulated kinase, phospho-c-JunN-terminal kinase), the expression of which was reduced by RLX. Pretreatment with estrogen receptor antagonists reversed the protective effects of RLX. GlcN can induce insulin resistance, β-cell dysfunction, and apoptosis in OVX rats and increase ER stress-related proteins in β-cells, whereas RLX can reverse these adverse effects. The effects of RLX act mainly through estrogen receptor α; therefore, RLX may be a candidate drug for postmenopausal women with OA and OP.

Pharmacotherapeutic options for the treatment of menopausal symptoms

Introduction: Menopausal symptoms can be very overwhelming for women. Over the years, many pharmacotherapeutic options have been tested, and others are still being developed. Hormone therapy (HT) is the most efficient therapy for managing vasomotor symptoms and related disturbances. The term HT comprises estrogens and progestogens, androgens, tibolone, the tissue-selective estrogen complex (TSEC), a combination of bazedoxifene and conjugated estrogens, and the selective estrogen receptor modulators, such as ospemifene. Estrogens and progestogens and androgens may differ significantly for chemical structure and can be delivered through different routes, thereby displaying various pharmacological and clinical properties. Tibolone, TSEC and SERM also exhibit unique pharmacodynamics that can be exploited to obtain distinctive therapeutic effects. Non-hormonal options fall mainly into the selective serotonin reuptake inhibitor (SSRI) and selective noradrenergic reuptake inhibitor (SNRI), GABA-analogue drug classes.Areas covered: Herein, the authors describe the pharmacokinetics and pharmacodynamics of hormonal (androgens, estrogens, progestogens, tibolone, TSEC, SERMs) and non-hormonal (SSRIs, SNRIs, Gabapentin, Pregabalin, Oxybutynin, Neurokinin antagonists) treatments for menopausal symptoms and report essential clinical trial data in humans.Expert opinion: Patient tailoring of treatment is key to managing symptoms of menopause. Physicians must have in-depth knowledge of the pharmacology of compounds to tailor therapy to the individual patient's characteristics and needs.

Skeletal Muscle Interleukin-6 Contributes to the Innate Immune Response in Septic Mice

ABSTRACT

Interleukin-6 (IL-6) is a major cytokine released by skeletal muscle. Although IL-6 plays complex but well-known roles in host defense, the specific contribution of skeletal muscle IL-6 to innate immunity remains unknown. We tested its functional relevance by exposing inducible skeletal muscle IL-6 knockdown (skmIL-6KD) mice to a cecal slurry model of polymicrobial peritonitis and compared responses to strain-matched controls and skeletal muscle Cre-matched controls at 3, 6, and 12 h postinfection. In both sexes, skmIL-6KD mice at 6 h of infection exhibited marked changes to leukocyte trafficking in the peritoneum, characterized by ∼1.75-fold elevation in %neutrophils, a ∼3-fold reduction in %lymphocytes and a ∼2 to 3-fold reduction in %basophils. A similar pattern was seen at 12 h. No changes were observed in plasma leukocyte counts. Circulating cytokines in female skmIL-6KD mice at 6 h consistently showed modest reductions in IL-6, but marked reductions in a broad range of both pro- and anti-inflammatory cytokines, e.g., TNFα and IL-10. In both sexes at 12 h, a generalized suppression of plasma cytokines was also seen after the effects of Cre-induction with raloxifene were addressed. There were no significant effects of skmIL-6KD on mortality in either sex. Collectively, our results are consistent with skmIL-6 playing an important and previously unrecognized role in immune cell trafficking and cytokine regulation during septic shock.

Primary Hyperparathyroidism: A Narrative Review of Diagnosis and Medical Management

Primary hyperparathyroidism (PHPT) is the most common cause of hypercalcemia in the outpatient setting. Symptomatic presentation includes non-specific signs and symptoms of hypercalcemia, skeletal fragility, nephrolithiasis and nephrocalcinosis. The majority of individuals present at an asymptomatic stage following routine biochemical screening, without any signs or symptoms of calcium or parathyroid hormone (PTH) excess or target organ damage. Indications for surgery have recently been revised as published in recent guidelines and consensus statements. Parathyroidectomy is advised in patients younger than 50 years old and in the presence of either significant hypercalcemia, impaired renal function, renal stones or osteoporosis. Surgery is always appropriate in suitable surgical candidates, however, medical management may be considered in those with mild asymptomatic disease, contraindications to surgery or failed previous surgical intervention. We summarized the optimal medical interventions available in the care of PHPT patients not undergoing parathyroidectomy. Calcium and vitamin D intake should be optimized. Antiresorptive therapy may be used for skeletal protection in patients with an increased fracture risk. Cinacalcet, a calcimimetic agent, has been shown to effectively lower serum calcium and PTH levels. The effect of medical treatment on the reduction in fracture risk is unknown and should be the focus of future research.

Green Nanotechnology in the Formulation of a Novel Solid Dispersed Multilayered Core-Sheath Raloxifene-Loaded Nanofibrous Buccal Film; In Vitro and In Vivo Characterization

Green nanotechnology utilizes the principles of green chemistry to formulate eco-friendly nanocarrier systems to mitigate patients and environment hazards. Raloxifene (RLX) demonstrates poor aqueous solubility (BCS class II) and low bioavailability, only 2% (extensive first-pass metabolism). The aim of this study is to enhance RLX solubility and bioavailability via development of novel solid dispersed multilayered core-sheath RLX-loaded nanofibers (RLX-NFs) without the involvement of organic solvents. A modified emulsion electrospinning technique was developed. Electrospinning of an RLX-nanoemulsion (RLX-NE) with polymer solution (poly vinyl alcohol (PVA), hydroxypropyl methylcellulose (HPMC), and chitosan (CS) in different volume ratios (1:9, 2:8, and 4:6) using D-optimal response surface methodology was adopted. In vitro characterization of RLX-loaded NFs was performed; scanning electron microscope (SEM), thermal analysis, drug content, release studies, and bioadhesion potential. The optimum NFs formula was evaluated for morphology using high-resolution transmission electron microscopy (HRTEM), and ex vivo drug permeation. The superiority of E2 (comprising RLX-NE and PVA (2:8)) over other NF formulae was statistically observed with respect to Q60 (56.048%), Q240 (94.612%), fiber size (594.678 nm), mucoadhesion time 24 h, flux (5.51 µg/cm2/h), and enhancement ratio (2.12). RLX pharmacokinetics parameters were evaluated in rabbits following buccal application of NF formula E2, relative to RLX oral dispersion. E2 showed significantly higher Cmax (53.18 ± 4.56 ng/mL), and relative bioavailability (≈2.29-fold).

Mg,Si-Co-Substituted Hydroxyapatite/Alginate Composite Beads Loaded with Raloxifene for Potential Use in Bone Tissue Regeneration

Osteoporosis is a worldwide chronic disease characterized by increasing bone fragility and fracture likelihood. In the treatment of bone defects, materials based on calcium phosphates (CaPs) are used due to their high resemblance to bone mineral, their non-toxicity, and their affinity to ionic modifications and increasing osteogenic properties. Moreover, CaPs, especially hydroxyapatite (HA), can be successfully used as a vehicle for local drug delivery. Therefore, the aim of this work was to fabricate hydroxyapatite-based composite beads for potential use as local carriers for raloxifene. HA powder, modified with magnesium and silicon ions (Mg,Si-HA) (both of which play beneficial roles in bone formation), was used to prepare composite beads. As an organic matrix, sodium alginate with chondroitin sulphate and/or keratin was applied. Cross-linking of beads containing raloxifene hydrochloride (RAL) was carried out with Mg ions in order to additionally increase the concentration of this element on the material surface. The morphology and porosity of three different types of beads obtained in this work were characterized by scanning electron microscopy (SEM) and mercury intrusion porosimetry, respectively. The Mg and Si released from the Mg,Si-HA powder and from the beads were measured by inductively coupled plasma optical emission spectrometry (ICP-OES). In vitro RAL release profiles were investigated for 12 weeks and studied using UV/Vis spectroscopy. The beads were also subjected to in vitro biological tests on osteoblast and osteosarcoma cell lines. All the obtained beads revealed a spherical shape with a rough, porous surface. The beads based on chondroitin sulphate and keratin (CS/KER-RAL) with the lowest porosity resulted in the highest resistance to crushing. Results revealed that these beads possessed the most sustained drug release and no burst release effect. Based on the results, it was possible to select the optimal bead composition, consisting of a mixture of chondroitin sulphate and keratin.

Green tea extract synergistically enhances the effectiveness of an antiresorptive drug on management of osteoporosis induced by ovariectomy in a rat model

Antiresorptive drugs are effective for reducing bone loss in postmenopausal women, but their long-term application may be associated with adverse effects. The present study aimed to investigate the potential in vivo synergistic effects of green tea extract (GTE) and alendronate or raloxifene on the management of osteoporosis. Ovariectomized rats were fed orally with GTE, alendronate and raloxifene at different concentrations and various combinations for 4 weeks. Bone mineral density (BMD) at the lumbar spine, femur and tibia was monitored weekly using peripheral quantitative computed tomography. Bone microarchitecture in the left distal femur was analyzed using micro-CT, while serum biochemical levels were measured using ELISA kits at the end of the study. GTE alone effectively mitigated BMD loss and improved bone microarchitecture in rats. The co-administration of GTE and alendronate increased total BMD in the lumbar spine, femur and tibia. Particularly, GTE synergistically enhanced the effect of alendronate at a low dose on bone microarchitecture and decreased serum tartrate-resistant acid phosphatase. These findings imply that the dosage of certain antiresorptive agents could be reduced when they are administrated simultaneously with GTE, so that their adverse effects are minimized. The findings may be used to support the development of a new synergistic intervention between food therapy and pharmacotherapy on the management of osteoporosis in a long-term basis.

Raloxifene, identified as a novel LSD1 inhibitor, suppresses the migration of renal cell carcinoma

Aim: As an important epigenetic modulator, histone lysine-specific demethylase 1 (LSD1) has been proved to be associated with the progression of renal cell carcinoma (RCC). Discovering novel LSD1 inhibitors offers therapeutic potential for RCC treatment. Methods & Results: We identified raloxifene as a novel LSD1 inhibitor (IC₅₀ = 2.08 μM) through small compound library screening. Molecular docking indicated raloxifene might bind LSD1 in the flavin adenine dinucleotide (FAD) binding cavity in a reversible manner. Cell viability and migration assays showed raloxifene could suppress the proliferation and migration of RCC cells bearing overexpressed LSD1. Conclusion: Our findings indicated that LSD1 might be a promising therapeutic target for RCC and that raloxifene could serve as a lead compound for further anti-RCC metastasis drug discovery.

Raloxifene is a Female-specific Proteostasis Therapeutic in the Spinal Cord

Several neurodegenerative disorders are characterized by proteasome dysfunctions leading to protein aggregations and pathogenesis. Since we showed that estrogen receptor alpha (ERα) activates the proteasome, drugs able to stimulate ERα in the central nervous system (CNS) could hold potential for therapeutic intervention. However, the transcriptional effects of selective estrogen receptor modulators (SERMs), such as tamoxifen and raloxifene, can be tissue specific. A direct comparison of the effects of different SERMs on gene transcription in the CNS has never been performed. Here, we report an RNA-seq analysis of the spinal cord treated with estrogen, tamoxifen, or raloxifene. We find stark SERM and sex-specific differences in gene expression profiles in the spinal cord. Notably, raloxifene, but not estrogen or tamoxifen, modulates numerous deubiquitinating enzymes, proteasome subunits and assembly factors, and these effects translate into decreased protein aggregates. In the SOD1-G93A mouse model of amyotrophic lateral sclerosis, we found that even a low dose of raloxifene causes a significant decrease in mutant SOD1 aggregates in the spinal cord, accompanied by a delay in the decline of muscle strength in females, but not in males. These results strongly indicate SERM-selective as well as sex-specific effects, and emphasize the importance of sex as a biological variable to be considered for the careful selection of specific SERM for use in clinical trials for neurodegenerative diseases.

Effects of Raloxifene Combined with Low-dose Conjugated Estrogen on the Endometrium in Menopausal Women at High Risk for Breast Cancer

OBJECTIVES

To compare the effects of low-dose conjugated estrogen (CE), raloxifene, and the combination thereof on the endometrium of postmenopausal women.

METHODS

Postmenopausal women between 45 and 60 years of age, with Gail score≥1.67 and no endometrial disorders, were randomly assigned to receive low-dose CE (0.3 mg), raloxifene (60 mg), or combined therapy for 1 year. Transvaginal ultrasound was performed at baseline and every 3 months; the Kupperman Index was assessed at baseline and every 6 months. Endometrial biopsies were performed if endometrial thickness (ET) was ≥5 mm or if vaginal bleeding occurred. The primary outcome was the occurrence of ET≥5 mm over the one-year period.

RESULTS

Seventy-three women were randomly assigned and analyzed on an intent-to-treat basis. Eight, three, and four women in the CE, raloxifene, and combination groups, respectively, exhibited ET≥5 mm. No genital bleeding was reported in the combination group. Endometrial biopsy revealed atrophy or polyps in all groups, with one patient in the CE group exhibiting a proliferative endometrium without atypia. At 6 months, there was a progressive increase in mean ET in the CE group, but not in the other two groups, with statistically significant differences at 6, 9, and 12 months. Mean scores for vasomotor symptoms and Kupperman Index favored the CE and combination groups over raloxifene.

CONCLUSION

Combined raloxifene and low-dose CE decreased the severity of menopausal symptoms to a similar extent as CE alone and had similar effects as raloxifene alone on the endometrium.

Raloxifene-induced osteonecrosis of the jaw (MRONJ) with no exposure to bisphosphonates: clinical and radiographic findings

Raloxifene is a selective estrogen receptor modulator (SERM) that is used to manage osteoporosis in women. Because of its tissue selectivity, raloxifene has fewer side effects than estrogen therapy; however, raloxifene-associated osteonecrosis of the jaw (ONJ) has recently been reported. While most of the reported cases were treated with antiresorptive therapy in addition to raloxifene, ONJ can also occur with the isolated use of raloxifene. This report presents a case where there was no prior exposure to bisphosphonates, in which the patient incidentally had florid cemento-osseous dysplasia (FCOD). Raloxifene-associated ONJ has never been reported before in a patient with FCOD. It is unclear whether the presence of FCOD increases the risk of ONJ. Case report: Clinical and radiographic findings regarding an African-American patient with FCOD and raloxifene-induced ONJ are described. The patient underwent a battery of investigations and surgical debridement of the area in question. She has remained disease free in the 2 years following the treatment. Conclusions: The aim of this report is to shed some light on a serious complication of raloxifene, a medication that is increasingly encountered in dental practices. Dental practitioners should use this knowledge to increase their awareness of possible ONJ development after the use of raloxifene. Brief recommendations and guidance in general dental practice for management of patients on raloxifene are also presented.

Raloxifene as a treatment option for viral infections

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused corona virus disease 2019 (COVID-19) pandemic and led to mass casualty. Even though much effort has been put into development of vaccine and treatment methods to combat COVID-19, no safe and efficient cure has been discovered. Drug repurposing or drug repositioning which is a process of investigating pre-existing drug candidates for novel applications outside their original medical indication can speed up the drug development process. Raloxifene is a selective estrogen receptor modulator (SERM) that has been approved by FDA in 1997 for treatment and prevention of postmenopausal osteoporosis and cancer. Recently, raloxifene demonstrates efficacy in treating viral infections by Ebola, influenza A, and hepatitis C viruses and shows potential for drug repurposing for the treatment of SARS-CoV-2 infection. This review will provide an overview of raloxifene's mechanism of action as a SERM and present proposed mechanisms of action in treatment of viral infections.

The Role of Estrogen Receptors and Their Signaling across Psychiatric Disorders

Increasing evidence suggests estrogen and estrogen signaling pathway disturbances across psychiatric disorders. Estrogens are not only crucial in sexual maturation and reproduction but are also highly involved in a wide range of brain functions, such as cognition, memory, neurodevelopment, and neuroplasticity. To add more, the recent findings of its neuroprotective and anti-inflammatory effects have grown interested in investigating its potential therapeutic use to psychiatric disorders. In this review, we analyze the emerging literature on estrogen receptors and psychiatric disorders in cellular, preclinical, and clinical studies. Specifically, we discuss the contribution of estrogen receptor and estrogen signaling to cognition and neuroprotection via mediating multiple neural systems, such as dopaminergic, serotonergic, and glutamatergic systems. Then, we assess their disruptions and their potential implications for pathophysiologies in psychiatric disorders. Further, in this review, current treatment strategies involving estrogen and estrogen signaling are evaluated to suggest a future direction in identifying novel treatment strategies in psychiatric disorders.

Discovery of a Bradykinin B2 Partial Agonist Profile of Raloxifene in a Drug Repurposing Campaign

Covid-19 urges a deeper understanding of the underlying molecular mechanisms involved in illness progression to provide a prompt therapeutical response with an adequate use of available drugs, including drug repurposing. Recently, it was suggested that a dysregulated bradykinin signaling can trigger the cytokine storm observed in patients with severe Covid-19. In the scope of a drug repurposing campaign undertaken to identify bradykinin antagonists, raloxifene was identified as prospective compound in a virtual screening process. The pharmacodynamics profile of raloxifene towards bradykinin receptors is reported in the present work, showing a weak selective partial agonist profile at the B2 receptor. In view of this new profile, its possible use as a therapeutical agent for the treatment of severe Covid-19 is discussed.

Development and validation of ultra-high-performance liquid chromatography-mass spectrometry method for the determination of raloxifene and its phase II metabolites in plasma: Application to pharmacokinetic studies in rats

The aim of this study is to establish a reliable liquid chromatography-mass spectrometry method to simultaneously quantitate raloxifene, and its major metabolites, raloxifene-6-glucuronide, raloxifene-4'-glucuronide, and raloxifene-6-sulfate in rat plasma samples for pharmacokinetic studies. The separation of the analytes was achieved on a Waters BEH C₁₈ column. Water (0.1% formic acid) and acetonitrile were used as the mobile phases for elution. A one-step protein precipitation using a mixture solvent was applied for plasma sample preparation. The method was validated following the FDA guidance. The results showed that the linear range were 1.95-1000 nM for raloxifene-6-glucuronide, and raloxifene-4'-glucuronide, 0.195-100 nM for raloxifene-6-sulfate, and 0.195-200 nM for raloxifene, respectively. The lower limit of quantification was 1.95, 1.95, 0.195, and 0.195 nM for raloxifene-6-glucuronide, raloxifene-4'-glucuronide, raloxifene-6-sulfate, and raloxifene, respectively. Only 20 µl of plasma sample was required since the method is sensitive. The intra- and interday variance is <15% and the accuracy is within 85-115%. The variance of matrix effect and recovery were <15%. The method was successfully applied in a pharmacokinetic study in rats with oral administration of raloxifene.

Photothermal Generation of Oxygen-Irrelevant Free Radicals with Simultaneous Suppression of Glutathione Synthesis for an Enhanced Photonic Thermodynamic Cancer Therapy

Reactive oxygen species (ROS) as one kind of oxygen-dependent toxic free radical has been widely adopted in ROS-mediated therapies (RMT). However, two shackles, known as tumor hypoxia and high intratumor glutathione (GSH) levels, respectively, limit RMT as the former prevents ROS from generating, while the latter scavenges the ROS generated. Herein, we developed a novel nanoplatform to simultaneously overcome the two shackles by facile preparation of mesoporous carbon nanospheres (MCNs) with AIBI and raloxifene loaded inside as an initiator and inhibitor, respectively, and phase-change materials (PCMs) capped outside as gatekeepers. Upon 808 nm NIR light irradiation, the photothermal effect of MCNs melted PCMs causing the loaded AIBI and raloxifene to be released, during which the AIBI was further decomposed into oxygen-irrelevant radicals to kill cancer cells, while the raloxifene suppressed GSH synthesis, synergistically enabling an enhanced photonic thermodynamic cancer therapy.

Randomized head-to-head comparison of minodronic acid and raloxifene for fracture incidence in postmenopausal Japanese women: the Japanese Osteoporosis Intervention Trial (JOINT)-04

AIMS

We conducted a head-to-head randomized trial of minodronate, a bisphosphonate, and raloxifene, a selective estrogen receptor modulator, to obtain clinical evidence and information about their efficacy and safety.

METHODS

The Japanese Osteoporosis Intervention Trial protocol number 4 (JOINT-04) trial is a multi-center, open-labeled, blinded endpoints, head-to-head randomized trial of minodronate and raloxifene. Ambulatory elderly women with osteoporosis (age, >60 years) were randomly allocated to the raloxifene or minodronate group by central registration. The co-primary endpoints included any one of osteoporotic fractures (vertebral, humeral, femoral, and radial fractures), vertebral fractures, and major osteoporotic fractures (clinical vertebral, humeral, femoral, and radial fractures). The biological effects of each drug, patients' quality of life, and drug safety were assessed based on the secondary outcomes. This study was registered at the University Hospital Medical Information Network-Clinical Trials Registry (UMIN-CTR) under trial identification number UMIN000005433.

RESULTS

A total of 3896 patients were randomized to the minodronate and raloxifene groups, and drug efficacy assessments were performed for 3247 patients (1623 and 1624 patients, respectively). Among these patients, 1176 and 1187 patients received allocated treatment for 2 years. The incidence rate ratios for osteoporotic, vertebral, and major osteoporotic fractures in the minodronate group were 0.94 (95% CI: 0.78-1.13, p = .494), 0.86 (95% CI: 0.70-1.05, p = .147), and 1.22 (95% CI: 0.86-1.74, p = .274), respectively. Compared to the raloxifene group, the minodronate group showed significantly increased bone mineral density of the lumbar spine for each visit (6 months: p = .007, 12 months: p = .0003, 24 months: p<.0001). Also, serious adverse reactions were observed for four and six patients in the minodronate and raloxifene groups, respectively.

CONCLUSIONS

Overall, there were no statistical differences in the incidence rates of osteoporotic, vertebral, or major osteoporotic fractures between the two groups. Serious adverse reactions were rare in both groups.

Raloxifene and n-Acetylcysteine Ameliorate TGF-Signalling in Fibroblasts from Patients with Recessive Dominant Epidermolysis Bullosa

Recessive dystrophic epidermolysis bullosa (RDEB) is a severe skin disease caused by mutation of the COL7A1 gene. RDEB is associated with high levels of TGF-β1, which is likely to be involved in the fibrosis that develops in this disease. Endoglin (CD105) is a type III coreceptor for TGF-β1 and its overexpression in fibroblasts deregulates physiological Smad/Alk1/Alk5 signalling, repressing the synthesis of TGF-β1 and extracellular matrix (ECM) proteins. Raloxifene is a specific estrogen receptor modulator designated as an orphan drug for hereditary hemorrhagic telangiectasia, a rare vascular disease. Raloxifene stimulates endoglin synthesis, which could attenuate fibrosis. By contrast, the antioxidant N-acetylcysteine may have therapeutic value to rectify inflammation, fibrosis and endothelial dysfunction. Thus, we present here a repurposing strategy based on the molecular and functional screening of fibroblasts from RDEB patients with these drugs, leading us to propose the repositioning of these two well-known drugs currently in clinical use, raloxifene and N-acetylcysteine, to counteract fibrosis and inflammation in RDEB. Both compounds modulate the profibrotic events that may ultimately be responsible for the clinical manifestations in RDEB, suggesting that these findings may also be relevant for other diseases in which fibrosis is an important pathophysiological event.