Efficacy and Tolerability of Topical 0.1% Stabilized Bioactive Retinol for Photoaging: A Vehicle-Controlled Integrated Analysis.

INTRODUCTION: Chronic exposure to ultraviolet light photoages skin. Retinol, a precursor molecule to retinoic acid that causes less irritation, is available as a nonprescription, cosmetic retinoid and improves collagen production, skin elasticity, and signs of photoaging. Advances in formulation science have allowed the production of stabilized bioactive retinol formulations. This integrated analysis aims to build on previous studies and further examine the comprehensive efficacy and tolerability of topical 0.1% stabilized bioactive retinol. METHODS: This analysis included 6 vehicle-controlled studies of 0.1% stabilized bioactive retinol in women with mild-to-moderate signs of photodamage. Across all studies, the same dermatologist investigator assessed overall photodamage; wrinkles on the forehead, cheeks, and undereye area; crow’s feet wrinkles and fine lines; lack of even skin tone; and brown spots at baseline and weeks 4, 8, and 12 on a numerical scale. Tolerability was also assessed. RESULTS: Participants (retinol, N=237; vehicle, N=234) had a mean (SD) age of 47.4 (6.6) years. Retinol induced greater improvements from baseline in all signs of photoaging vs vehicle as early as week 4 and through 12 weeks of application. Few participants experienced irritation; all events were mild to moderate and transient. The most common signs of irritation were erythema (n=2) and skin scaling/peeling (n=5). CONCLUSIONS: This pooled analysis of 6 vehicle-controlled clinical studies provides new evidence for the efficacy of 0.1% stabilized bioactive retinol in improving signs of photoaging without causing major irritation. Topical 0.1% stabilized bioactive retinol was well tolerated with only a few reported cases of skin irritation. J Drugs Dermatol. 2024;23(4):     doi:10.36849/JDD.8124.

Superiority of anthracycline-free treatment in standard-risk acute promyelocytic leukemia: A systematic review and comparative epidemiological analysis.

BACKGROUND: Recent advances in the treatment of acute promyelocytic leukemia (APML) have seen unprecedented improvements in patient outcomes. However, such rapid growth in understanding often leads to uncertainty regarding superiority among candidate treatment regimens, especially when further scrutinized from an epidemiological perspective. AIMS: The aim of this systematic review with epidemiological analysis was to identify and compare commonly utilized protocols for standard-risk APML with a particular focus on complete remission (CR), overall/disease-free survival (DFS), and reported adverse events. METHODS AND RESULTS: Medline, Scopus, and CINAHL were interrogated to identify studies utilizing all-trans retinoic acid (ATRA) in addition to arsenic trioxide (ATO) and/or anthracyclines such as idarubicin (IDA) in the treatment of de-novo APML. After collation of studies, an epidemiological analysis was subsequently performed to compare protocols with regards to outcomes of interest using number needed to benefit (NNB) and number needed to harm (NNH) measures. Seventeen articles, describing 12 distinct trials, were included in the analysis. These trials made use of three unique protocols; CR rates were 94%-100% for ATO/ATRA regimens, 95%-96% for ATO/ATRA/anthracycline regimens, and 89%-94% for ATRA/anthracycline regimens. Epidemiological analysis demonstrated NNB for CR was 9.09 (ATO/ATRA vs. ATRA/IDA) and 20.00 (ATO/ATRA vs. ATO/ATRA/IDA), NNH for neutropenia was -3.45 (ATO/ATRA vs. ATRA/IDA), and NNH for infection was -3.13 (ATO/ATRA vs. ATRA/IDA) and -1.89 (ATO/ATRA vs. ATO/ATRA/IDA). CONCLUSION: The ATO/ATRA regimen is superior to chemotherapy-containing protocols at inducing remission and promoting survival in patients with APML. The regimen is better tolerated than the proposed alternatives with fewer adverse events. Future research opportunities include quantifying APML epidemiology and pursuing oral arsenic as an option for simplification of therapeutic protocols.

Acute kidney injury in acute promyelocytic leukemia: a possible adverse effect of high dose arsenic trioxide in obese patients.

Arsenic trioxide (ATO)-based regimens are standard in acute promyelocytic leukemia (APL). ATO-related nephrotoxicity has not been reported. We reviewed APL patients treated with ATO to identify cases of acute kidney injury (AKI). Clinically significant cases were characterized. Multivariate analysis was performed to identify predictors of idiopathic, clinically significant AKI. One hundred and eight patients were included. ATO dose was 0.15 mg/kg/day using actual body weight with no dose cap. Thirty-one (28.7%) AKI cases were identified, 10 (32.3%) clinically significant. Six were idiopathic; five required dialysis. The proportion with significant, idiopathic AKI was 15.8% in patients receiving >15mg ATO versus 0% in those receiving ≤15mg (p = 0.001). On multivariate analysis, only ATO dose was a significant predictor of clinically significant AKI (odds ratio of 1.91, 95%CI, 1.19-3.07, p = 0.007). High-dose ATO may be associated with significant nephrotoxicity. We recommend that ATO dose be capped at 15 mg to minimize toxicity for this curable disease.

Single-cell Transcriptomics Reveals Activation of Macrophages in All-trans Retinoic Acid (atRA)-induced Cleft Palate.

Cleft palate is among the most common birth defects with an impact on swallowing and speaking and is difficult to diagnose with ultrasound during pregnancy. In this study, we systematically capture the cellular composition of all-trans retinoic acid (atRA)-exposed and normal embryonic gestation 16.5 days mouse palate by the single-cell RNA sequencing technique. The authors identified 14 major cell types with the largest proportion of fibroblasts. The proportion of myeloid cells in atRA-exposed palate was markedly higher than those in the normal palate tissue, especially M1-like macrophages and monocytes. The upregulated genes of the different expression genes between atRA-exposed palate and normal palate tissue were linked to the biological processes of leukocyte chemotaxis and migration. Protein TLR2, CXCR4, THBS1, MRC1, transcription factor encoding genes Cebpb, Fos, Jun, Rela, and signaling pathway IL-17 and phagosome were found to be significantly involved in these processes. Subsequently, cellular communication network analysis suggested that myeloid-centered cell interactions SELL, SELPLG, MIF, CXCL, ANNEXIN, THBS, and NECTIN were significantly more activated in atRA-exposed palate. Overall, we delineate the single-cell landscape of atRA-induced cleft palate, revealing the effects of overexposure to atRA during palate tissue development and providing insights for the diagnosis of cleft palate.

Protective effect of tretinoin derivative and TXNRD1 protein on streptozotocin induced gestational diabetes via an age-rage signaling-pathway.

BACKGROUND: In the present study effect of tretinoin derivative was investigated on the pathogenesis of gestational diabetes mellitus (GDM) in mice model in vivo. MATERIALS AND METHODS: Diabetes was induced in mice by injecting Streptozotocin (STZ) for 5consecutive days at a dose of 65 mg/kg body weight through the intraperitoneal route. Tretinoin derivative was given to the mice at 0.12 and 0.25 mg/kg doses through gavage in normal saline alternately for one week after STZ injection. RESULTS: The results demonstrated that tretinoin derivative administration to the diabetic mice significantly (P<0.05) alleviated the blood FBG and FINS levels. Administration of tretinoin derivative to the diabetic mice significantly (P<0.05) promoted the blood HDL level and alleviated TC and TG levels. The administration of tretinoin derivative to the diabetic mice significantly (P<0.05) alleviated the CRP, IL-6and TNF-α production in pancreatic tissues. Tretinoin derivative administration to the diabetic mice significantly (P<0.05) elevated the SOD activity, and CAT level and lowered the MDA level in pancreatic tissues. The TXNRD1 expression in diabetic mice was comparable to that in the normal group after administration of tretinoin derivativeat the dose of 0.25 mg/kg dose. In silico data demonstrated that tretinoin derivativeinteracts with TXNRD1 protein with the binding affinity ranging from -10 to 9.4 kcal/ mol. CONCLUSION: In conclusion, tretinoin derivative administration effectively regulated streptozotocin-induced changes in fasting blood glucose, insulin level, high-density lipid level and triglyceride level in diabetic mice in vivo. The streptozotocin-induced excessive production of C-reactive protein and inflammatory cytokines was also down-regulated in diabetic mice on administration of tretinoin derivative. Therefore, tretinoin derivative can be investigated further as a therapeutic agent for the treatment of gestational diabetes mellitus.

Associations between the proliferation of palatal mesenchymal cells, Tgfß2 promoter methylation, Meg3 expression, and Smad signaling in atRA-induced cleft palate.

All-trans retinoic acid (atRA) is a teratogen that can induce cleft palate formation. During palatal development, murine embryonic palate mesenchymal (MEPM) cell proliferation is required for the appropriate development of the palatal frame, with Meg3 serving as a key regulator of the proliferative activity of these cells and the associated epithelial-mesenchymal transition process. DNA methylation and signaling via the TGFß/Smad pathway are key in regulating embryonic development. Here, the impact of atRA on MEPM cell proliferation and associations between Tgfß2 promoter methylation, Meg3, and signaling via the Smad pathway were explored using C57BL/6 N mice treated with atRA (100 mg/kg) to induce fetal cleft palate formation. Immunohistochemistry and BrdU assays were used to detect MEPM proliferation and DNA methylation assays were performed to detect Tgfß2 promoter expression. These analyses revealed that atRA suppressed MEPM cell proliferation, promoted the upregulation of Meg3, and reduced the levels of Smad2 and Tgfß2 expression phosphorylation, whereas Tgfß2 promoter methylation was unaffected. RNA immunoprecipitation experiments indicated that the TgfßI receptor is directly targeted by Meg3, suggesting that the ability of atRA to induce cleft palate may be mediated through the Tgfß/Smad signaling pathway.

Retinoic acid ameliorates low-grade endotoxemia-induced mastitis by limiting inflammatory responses in mice.

Mastitis is a serious disease for humans and animals, which causes huge economic losses in the dairy industry and is hard to prevent due to the complex and unclear pathogenesis. Subacute ruminal acidosis (SARA) has contributed to the development of mastitis by inducing ruminal dysbiosis and subsequent low-grade endotoxemia (LGE), however, how ruminal metabolic changes regulate this progress is still unclear. Our previous study revealed that cows with SARA had increased ruminal retinoic acid (RA) levels, a metabolic intermediate of vitamin A that plays an essential role in mucosal immune responses. Hence, the aim of this study was to investigate the protective effect of RA on LGE-induced mastitis and the underlying mechanisms in mice. The results showed that RA alleviated LGE-induced mastitis, as evidenced by RA significantly reduced the increase in mammary proinflammatory cytokines and improved blood-milk barrier injury caused by LGE. In addition, RA increased the expression of tight junction proteins, including ZO-1, occludin and claudin-3. Furthermore, we found that RA limited the mammary inflammatory responses by inhibiting the activation of NF-κB and NLRP3 signaling pathways. These findings suggest that RA effectively alleviates LGE-induced mastitis and implies a potential strategy for the treatment and prevention of mastitis and other diseases.

Treating low- and intermediate-risk acute promyelocytic leukemia with and without chemotherapy: A comparison in a tertiary care center.

Background: Acute promyelocytic leukemia (APL) comprises approximately 10% of acute myeloid leukemia (AML) cases. Material and Methods: Both options of treatment (ATRA-ATO and ATRA-chemotherapy) were discussed with patients with low- and intermediate-risk APL, pros and cons explained in details, and treatment regimen selected after getting informed written consent. Results: Total 71 patients were included in the study; among these patients, 3 were negative for both FISH for t (15,17) and RT-PCR for promyelocytic leukemia retinoic acid receptor alpha, and 36 patients with APL had white blood cell count at diagnosis >10 × 109/l. Total 30 patients with newly diagnosed as low- and intermediate-risk-APL fulfilled all inclusion criteria, treated and followed for a minimum period of 2 years up to June, 2016. Fifteen patients liked to be treated with all-trans retinoic acid (ATRA) and arsenic trioxide (ATO), while rest of the 15 patients preferred treatment with ATRA and chemotherapy. Conclusion: Combination of ATRA and ATO is equally effective, less toxic, and more feasible in comparison to ATRA and chemotherapy for patients with low- and intermediate-risk APL and is a viable option for this subset of patients, especially in countries with limited resources.

Topical Treatments for Photoaged Skin.

BACKGROUND: Photoaging due to cumulative lifetime ultraviolet light exposure is the greatest contributing factor to facial aging. With the continued growth of the population of individuals aged ≥65 years and over, demand for safe and effective photoaging treatments will likely increase. METHODS: This qualitative review provides an overview of efficacy and safety of over-the-counter (OTC) and prescription topical treatments for photoaging, including recent data from an investigator-initiated trial of the topical retinoid tazarotene. RESULTS: OTC and cosmeceutical products comprise the majority of treatment options for photoaging, although clinical data in support of their efficacy are generally lacking. Topical retinoids have been shown to increase collagen and elastic fibers and normalize melanocytes and keratinocytes, yielding improvements in wrinkling, texture, elasticity, and skin tone. Prescription topical retinoids (adapalene, tazarotene, tretinoin) are the most studied and efficacious treatments for photoaging, though their use is typically associated with adverse effects such as erythema, peeling, dryness, and burning/stinging in a concentration-dependent manner. In a 12-week, open-label study, lower-dose tazarotene 0.045% lotion led to significantly reduced signs and severity of photoaging vs baseline. CONCLUSION: Prescription topical retinoids are the most potent treatment option for photoaging, though their use may be limited by irritation concerns. Tazarotene 0.045% polymeric emulsion lotion has recently demonstrated significant photoaging improvements with 12 weeks of once-daily treatment, with a favorable safety and tolerability profile. CITATION: Sadick N, Pannu S, Abidi Z, et al. Topical treatments for photoaged skin. J Drugs Dermatol. 2023;22(9):867-873. doi:10.36849/JDD.7753.

Efficacy and safety of a novel triple combination cream compared to Kligman's trio for melasma: A 24-week double-blind prospective randomized controlled trial.

BACKGROUND: Kligman's trio (KT), combining hydroquinone, retinoic acid and corticosteroid, is considered as the gold standard treatment of melasma. Its efficacy has never been matched before, but it is tempered by frequent adverse effects. OBJECTIVE: To assess the efficacy and tolerance of a New Trio (NT) combination with isobutylamido-thiazolyl-resorcinol, retinoic acid and cortosteroid compared to KT. METHODS: We conducted a 24-week monocentric trial, randomized, double-blind, controlled versus KT, with 40 melasma patients. NT and KT were applied for 12 weeks and associated with the same sunscreen applied for 24 weeks. The primary endpoint was the modified Melasma Area Severity Index (mMASI) at 12 weeks. Patient quality of life was investigated using MelasQoL. RESULTS: After 12 weeks, KT and NT groups both demonstrated a significant improvement in mMASI, respectively -2.84 (SE 0.69, p < 0.0002) and -4.33 (SE 0.71, p < 0.0001). The mean difference between the two groups was -1.49 (IC 95% -3.52 to 0.54, p = 0.14). MelasQoL improvement was -6.66 (SE 3.29, p = 0.0515) with KT and -12.57 (SE 3.29, p = 0.0006) with NT. CONCLUSION: The NT combination appears to be an effective treatment option for treating melasma and could be considered as a well-tolerated alternative to KT.

Homoharringtonine-Based Induction Regimen Improved the Remission Rate and Survival Rate in Chinese Childhood AML: A Report From the CCLG-AML 2015 Protocol Study.

PURPOSE: Homoharringtonine (HHT) is commonly used for the treatment of Chinese adult AML, and all-trans retinoic acid (ATRA) has been verified in acute promyelocytic leukemia (APL). However, the efficacy and safety of HHT-based induction therapy have not been confirmed for childhood AML, and ATRA-based treatment has not been evaluated among patients with non-APL AML. PATIENTS AND METHODS: This open-label, multicenter, randomized Chinese Children's Leukemia Group-AML 2015 study was performed across 35 centers in China. Patients with newly diagnosed childhood AML were first randomly assigned to receive an HHT-based (H arm) or etoposide-based (E arm) induction regimen and then randomly allocated to receive cytarabine-based (AC arm) or ATRA-based (AT arm) maintenance therapy. The primary end points were the complete remission (CR) rate after induction therapy, and the secondary end points were the overall survival (OS) and event-free survival (EFS) at 3 years. RESULTS: We enrolled 1,258 patients, of whom 1,253 were included in the intent-to-treat analysis. The overall CR rate was significantly higher in the H arm than in the E arm (79.9% v 73.9%, P = .014). According to the intention-to-treat analysis, the 3-year OS was 69.2% (95% CI, 65.1 to 72.9) in the H arm and 62.8% (95% CI, 58.7 to 66.6) in the E arm (P = .025); the 3-year EFS was 61.1% (95% CI, 56.8 to 65.0) in the H arm and 53.4% (95% CI, 49.2 to 57.3) in the E arm (P = .022). Among the per-protocol population, who received maintenance therapy, the 3-year EFS did not differ significantly across the four arms (H + AT arm: 70.7%, 95% CI, 61.1 to 78.3; H + AC arm: 74.8%, 95% CI, 67.0 to 81.0, P = .933; E + AC arm: 72.9%, 95% CI, 65.1 to 79.2, P = .789; E + AT arm: 66.2%, 95% CI, 56.8 to 74.0, P = .336). CONCLUSION: HHT is an alternative combination regimen for childhood AML. The effects of ATRA-based maintenance are comparable with those of cytarabine-based maintenance therapy.

Acyclic retinoid peretinoin reduces hemorrhage-associated brain injury in vitro and in vivo.

Peretinoin is an acyclic retinoid that stimulates retinoic acid receptors (NR1Bs) and produces therapeutic effects on hepatocellular cancer. We have previously shown that NR1B agonists such as Am80 and all trans-retinoic acid suppress pathogenic events in intracerebral hemorrhage. The present study addressed the actions of peretinoin and Am80 against cytotoxicity of a blood protease thrombin on cortico-striatal slice cultures obtained from neonatal rat brains. Application of 100 U/ml thrombin to the slice cultures for 72 h caused cell death in the cortical region and tissue shrinkage in the striatal region. Peretinoin (50 µM) and Am80 (1 µM) counteracted these cytotoxic effects of thrombin, and the effect of peretinoin and Am80 was blocked by LE540, an NR1B antagonist. A broad-spectrum kinase inhibitor K252a (3 µM) attenuated the cytoprotective effect of peretinoin in the cortical region, whereas a specific protein kinase A inhibitor KT5720 (1 µM) attenuated the protective effect of peretinoin in the cortical and the striatal regions. On the other hand, nuclear factor-κB (NF-κB) inhibitors such as pyrrolidine dithiocarbamate (50 µM) and Bay11-7082 (10 µM) prevented thrombin-induced shrinkage of the striatal region. Peretinoin and Am80 as well as Bay11-7082 blocked thrombin-induced nuclear translocation of NF-κB in striatal microglia and loss of striatal neurons. We also found that daily administration of peretinoin reduced histopathological injury and alleviated motor deficits in a mouse model of intracerebral hemorrhage. These results indicate that NR1B agonists including peretinoin may serve as a therapeutic option for hemorrhagic brain injury.

Genital ulcers following all-trans-retinoic acid therapy: A case series with review of literature.

All-trans-retinoic acid (ATRA) has transformed the treatment of acute promyelocytic leukemia. Most of the adverse effects associated with this drug are minor barring differentiation syndromes. Genital ulcers feature among the underreported adverse effects of ATRA which needs to be kept in mind to avoid life-threatening complications. We describe two cases who developed genital ulcers while treated with ATRA.

Serum metabolomic profiling reveals potential biomarkers in systemic sclerosis.

BACKGROUND: Systemic sclerosis (SSc) is a chronic and systemic autoimmune disease marked by the skin and visceral fibrosis. Metabolic alterations have been found in SSc patients; however, serum metabolomic profiling has not been thoroughly conducted. Our study aimed to identify alterations in the metabolic profile in both SSc patients before and during treatment, as well as in mouse models of fibrosis. Furthermore, the associations between metabolites and clinical parameters and disease progression were explored. METHODS: High-performance liquid chromatography quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS)/MS was performed in the serum of 326 human samples and 33 mouse samples. Human samples were collected from 142 healthy controls (HC), 127 newly diagnosed SSc patients without treatment (SSc baseline), and 57 treated SSc patients (SSc treatment). Mouse serum samples were collected from 11 control mice (NaCl), 11 mice with bleomycin (BLM)-induced fibrosis and 11 mice with hypochlorous acid (HOCl)-induced fibrosis. Both univariate analysis and multivariate analysis (orthogonal partial least-squares discriminate analysis (OPLS-DA)) were conducted to unravel differently expressed metabolites. KEGG pathway enrichment analysis was performed to characterize the dysregulated metabolic pathways in SSc. Associations between metabolites and clinical parameters of SSc patients were identified by Pearson's or Spearman's correlation analysis. Machine learning (ML) algorithms were applied to identify the important metabolites that have the potential to predict the progression of skin fibrosis. RESULTS: The newly diagnosed SSc patients without treatment showed a unique serum metabolic profile compared to HC. Treatment partially corrected the metabolic changes in SSc. Some metabolites (phloretin 2'-O-glucuronide, retinoyl b-glucuronide, all-trans-retinoic acid, and betaine) and metabolic pathways (starch and sucrose metabolism, proline metabolism, androgen and estrogen metabolism, and tryptophan metabolism) were dysregulated in new-onset SSc, but restored upon treatment. Some metabolic changes were associated with treatment response in SSc patients. Metabolic changes observed in SSc patients were mimicked in murine models of SSc, indicating that they may reflect general metabolic changes associated with fibrotic tissue remodeling. Several metabolic changes were associated with SSc clinical parameters. The levels of allysine and all-trans-retinoic acid were negatively correlated, while D-glucuronic acid and hexanoyl carnitine were positively correlated with modified Rodnan skin score (mRSS). In addition, a panel of metabolites including proline betaine, phloretin 2'-O-glucuronide, gamma-linolenic acid and L-cystathionine were associated with the presence of interstitial lung disease (ILD) in SSc. Specific metabolites identified by ML algorithms, such as medicagenic acid 3-O-b-D-glucuronide, 4'-O-methyl-(-)-epicatechin-3'-O-beta-glucuronide, valproic acid glucuronide, have the potential to predict the progression of skin fibrosis. CONCLUSIONS: Serum of SSc patients demonstrates profound metabolic changes. Treatment partially restored the metabolic changes in SSc. Moreover, certain metabolic changes were associated with clinical manifestations such as skin fibrosis and ILD, and could predict the progression of skin fibrosis.

An optimal combination of five main monomer components in Wuzi Yanzong Pill that prevents neural tube defects and reduces apoptosis and oxidative stress.

ETHNOPHARMACOLOGICAL RELEVANCE: Wuzi Yanzong Pill (WYP) is a classic traditional Chinese medicine (TCM) formula that is used for reproductive system diseases. Previous studies showed that WYP had a preventive effect on the development of neural tube defects (NTDs) induced by all-trans retinoic acid (atRA) in mice. AIM OF THE STUDY: This study aimed to determine the optimal combination of main monomer components in WYP on preventing NTDs and to understand the underlying mechanism. MATERIALS AND METHODS: An optimal combination was made from five representative components in WYP including hyperoside, acteoside, schizandrol A, kaempferide and ellagic acid by orthogonal design method. In a mouse model of NTDs induced by intraperitoneal injection of atRA, pathological changes of neural tube tissues were observed by Hematoxylin & Eosin (HE) staining, neural tube epithelial cells apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL), protein changes related to apoptosis, anti-apoptosis, and antioxidant factors were detected with Western blot. Potential targets and mechanisms of monomer compatibility group (MCG) acting on NTDs were analyzed by bioinformatics. RESULTS: Treatment with different combinations of WYP bioactive ingredients resulted in varying decreases in the incidence of NTDs in mice embryos. The combination of MCG15 (200 mg/kg of hyperoside, 100 mg/kg of acteoside, 10 mg/kg of schizandrol A, 100 mg/kg of kaempferide and 1 mg/kg of ellagic acid) showed the most significant reduction in NTD incidence. Mechanistically, MCG15 inhibited apoptosis and oxidative stress, as evidenced by reduced TUNEL-positive cells, downregulation of caspase-9, cleaved caspase-3, Bad, and Bax, and upregulation of Bcl-2, as well as decreased MDA and increased SOD, CAT, GSH, HO-1, and GPX1 levels. Bioinformatics analysis showed that MCG15 acted on the PI3K/Akt signaling pathway, which was confirmed by Western blot analysis showing increased expression of p-PI3K, p-Akt/Akt, and Nrf2 related indicators. CONCLUSION: We have identified an optimal combination of five bioactive components in WYP (MCG15) that prevented NTDs in mice embryos induced by atRA by activating the PI3K/Akt signaling pathway and inhibiting apoptosis and oxidative stress.

MTHFD1 is critical for the negative regulation of retinoic acid receptor signalling in anencephaly.

Neural tube defects are the most severe congenital malformations that result from failure of neural tube closure during early embryonic development, and the underlying molecular mechanisms remain elusive. Retinoic acid, an active derivative of vitamin A, is critical for neural system development, and retinoic acid receptor (RAR) signalling malfunctions have been observed in human neural tube defects. However, retinoic acid-retinoic acid receptor signalling regulation and mechanisms in neural tube defects are not fully understood. The mRNA expression of RARs and retinoid X receptors in the different human neural tube defect phenotypes, including 11 pairs of anencephaly foetuses, 10 pairs of hydrocephalus foetuses and nine pairs of encephalocele foetuses, was investigated by NanoString nCounter technology. Immunoprecipitation-mass spectrometry was performed to screen the potential interacting targets of retinoic acid receptor γ. The interactions between proteins were confirmed by co-immunoprecipitation and immunofluorescence laser confocal microscopy. Luciferase and chromatin immunoprecipitation with quantitative real-time polymerase chain reaction assays were used to clarify the underlying mechanism. Moreover, a neural tube defect animal model, constructed using excess retinoic acid, was used for further analysis with established molecular biology technologies. We report that level of retinoic acid receptor γ (RARγ) mRNA was significantly upregulated in the brain tissues of human foetuses with anencephaly. To further understand the actions of retinoic acid receptor γ in neural tube defects, methylenetetrahydrofolate dehydrogenase 1 was identified as a specific retinoic acid receptor γ target from IP-MS screening. Additionally, methylenetetrahydrofolate dehydrogenase 1 negatively regulated retinoic acid receptor γ transcription factor activity. Furthermore, low expression of methylenetetrahydrofolate dehydrogenase 1 and activation of retinoic acid receptor signalling were further determined in human anencephaly and a retinoic acid-induced neural tube defect mouse model. This study reveals that methylenetetrahydrofolate dehydrogenase 1, the rate-determining enzyme in the one-carbon cycle, might be a specific regulator of retinoic acid receptors; these findings provide new insights into the functional linkage between nuclear folate metabolism and retinoic acid receptor signalling in neural tube defect pathology.

[Devil with angel wings - when vitamin A saves lives]. / Teufel mit Engelsflügeln ­ wenn Vitamin A Leben rettet.

ANAMNESIS AND CLINICAL EXAMINATION: A 40-year-old male patient presented to our emergency department with a new onset of hemorrhagic diathesis. Clinically, there were marked bleeding stigmata with extensive ecchymosis in the thigh area and oral mucosal hemorrhage with otherwise general well-being. DIAGNOSTICS: The coagulation diagnostics performed were consistent with the picture of disseminated intravascular consumption coagulopathy. Microscopic blood count also revealed 74% morphologically atypical promyelocytes. DIAGNOSIS, THERAPY, AND CLINICAL COURSE: Bone marrow investigation confirmed the diagnosis of a microgranular variant of acute promyelocytic leukemia. In addition to coagulation optimization, therapy with all-trans retinoic acid (ATRA) was initiated immediately. Subsequently, arsenic trioxide (ATO) and the anthracycline idarubicin were added. No severe complications occurred in the following course of treatment. Moreover, the patient is currently in complete remission regarding acute promyelocytes leukemia. CONCLUSIONS: Acute promyelocytic leukemia accounts for approximately 10-15% of all acute myeloid leukemias. Often, association with marked coagulation abnormalities due to disseminated intravascular consumption coagulopathy, which is present at diagnosis, APL becomes fatal if untreated. Rapid therapy initiation with ATRA and coagulation optimization, initiated as soon as the diagnosis is suspected, are crucial for prognosis.

Expression and function of patatin-like phospholipase domain-containing 2 in cleft palate induced by retinoic acid.

Cleft palate is a common maxillofacial congenital malformation, and its mechanism still has not been fully illustrated. Recently, lipid metabolic defects have been observed in cleft palate. Patatin-like phospholipase domain-containing 2 (Pnpla2) is an important lipolytic gene. However, its effect on the formation of cleft palate remains unknown. In this research, we explored the expression of Pnpla2 in the palatal shelves of control mice. We also studied mice with cleft palates induced by retinoic acid and its effect on the embryonic palatal mesenchyme (EPM) cells phenotype. We found that Pnpla2 was expressed in the palatal shelves of both the cleft palate and control mice. Pnpla2 expression was lower in cleft palate mice than in the control mice. Experiments with EPM cells showed that knockdown of Pnpla2 inhibited cell proliferation and migration. In conclusion, Pnpla2 is linked to palatal development. We have indicated that low expression of Pnpla2 affects palatogenesis by inhibiting the proliferation and migration of EPM cells.