All-trans Retinoic Acid Group Research Articles

All-trans-retinoic acid and valproic acid: A combinatorial approach for the treatment of nephrotic syndrome

Massive proteinuria, oedema, hypoalbuminemia, and hyperlipidemia are the hallmarks of nephrotic syndrome (NS). Recently, epigenetic pathways in renal diseases have been identified. The present work hypothesizes using the combination of two epigenetic drugs all-trans retinoic acid (ATRA) and valproic acid (VPA) as a prospective treatment method to lessen NS-related glomerulosclerosis, fibrosis, and increased renal function parameters along with attenuating inflammation and improving overall mitochondrial health. To induce NS, doxorubicin (8.5 mg/kg, n = 6) was injected intravenously into female Sprague Dawley rats. After 28 days, ATRA and VPA were orally administered to the rats, alone and in combination at a dose of 5 mg/kg (n = 6) and 200 mg/kg (n = 6) in sesame oil and saline, respectively. Prednisolone (3 mg/kg in saline; n = 6) was used as standard. Following 21-daytreatment period, the rats were sacrificed prior to which 24hrs urine samples were obtained. Blood samples were collected and kidneys were extracted for further analyses. Renal function parameters (proteinuria, BUN, albumin, creatinine), levels of tissue reengineering and fibrosis markers (TGF-β, MMP2 activity), cholesterol and triglyceride levels were significantly improved in the ATRA and VPA combination group as compared to positive control group. Histopathological analyses revealed a reduction in inflammation, glomerulosclerosis and fibrosis. The inflammatory markers, namely TNF-α, IL-1β, IL-6, NF-κB, determined by ELISA were downregulated. Mitochondrial biogenesis markers viz. PGC-1α, TFAM, NRF1, Nrf2, PPAR-γ, KEAP-1, analysed by RT-qPCR were upregulated thereby showing a significant improvement in the combination group as compared to positive control and standard group. The study overall contributes to a novel approach to treating NS and our findings will surely drive additional exploratory preclinical and clinical studies.

Biomarker MSC-C5b-9-Guided Master Therapies for Resistant/Recurrent ITP: A Prospective, Randomized, Open-Label, Multicenter Trial

Introduction: Immune thrombocytopenia (ITP) is an acquired organ-specific autoimmune disorder and a common bleeding disorder that poses a considerable risk to human health. Steroids, as the first-line treatment, do not provide long-term relief. Our previous clinical trials have confirmed the efficacy and safety of all-trans retinoic acid (ATRA) in the treatment of ITP and identified that the biomarker MSC-C5b-9 may be a stratification marker for evaluating the efficacy of ATRA (Haematologica, 2019; Lancet Haematol. 2017; 2021). This research aims to develop a new treatment approach for steroid-resistant/recurrent ITP based on the marker MSC-C5b-9. Method: We conducted a prospective, randomized, open-label, multicenter trial to evaluate the efficacy and safety of ATRA combined with eltrombopag based on MSC-C5b-9 as a novel treatment for steroid-resistant/recurrent ITP. Following enrollment, all patients underwent bone marrow aspiration to assess MSC-C5b-9 levels. Subsequently, patients were randomly assigned in a 1:1 ratio to either the eltrombopag group or the eltrombopag + ATRA group. In both treatment groups, the initial dose of eltrombopag was 50 mg daily, with dose adjustments based on platelet levels. For patients assigned to the ATRA group, ATRA was given at a dose of 10 mg twice daily. Peripheral blood cell counts and adverse drug reactions were regularly monitored. The primary endpoint was the sustained response rate at 18 months after randomization, and secondary endpoints include Complete Remission, Partial Remission, Relapse rate, Early Response, Initial Response, Adverse Events, and Adverse Events graded using the National Cancer Institute Common Terminology Criteria (NCI CTCAE) v5.0 criteria. The study has been registered at clinicaltrials.gov. NCT05438875. Result: From March 2023 to July 2023, a total of 30 patients with steroid-resistant/recurrent ITP were enrolled in the study and randomized 1:1 to receive eltrombopag combined with ATRA (ATRA group, n=15, MSC-C5b-9 +6, -9) or eltrombopag alone (control group, n=15, MSC-C5b-9 +6, -9) in 5 centers, and all enrolled patients were included in the intention-to-treat (ITT) analysis. In the ATRA group, the median age was 38 years (range, 29-64), consisting of 8 male patients. In the control group, the median age was 44 years (range, 23-75), consisting of 9 male patients. There were no statistically significant differences observed in the baseline clinical characteristics between the two groups. There was no difference in the bleeding score and ECOG score between the two groups (P=0.717; P=1.000). The median platelet count was comparable between the ATRA group and the control group (17 (1-28) vs. 16 (2-26), P=0.850). Comorbidities at random, such as hypertension, were comparable between the two groups (26.7% (4/15) vs. 33.3% (5/15), P=1.000). Combined autoantibody abnormalities were compared between the two groups (6.7% (1/15) vs. 6.7% (1/15), P=1.000). The rate of Early Response in the ATRA group was higher than that in the control group, but the difference was not significant (73.3% (11/15) vs. 53.5% (8/15), P=0.256). As of July 29, 2023, a total of 24 patients had been enrolled for a duration exceeding 4 weeks. Similarly, the Initial Response rate was higher in the ATRA group, but no significant difference was observed between the two groups (84.6% (11/13) vs. 63.6% (7/11), P=0.357). Nevertheless, it is noteworthy that the 4-week CR rate in the ATRA group was higher than that in the control group (76.9% (10/13) vs. 36.4% (4/11), P=0.045). What's more, the overall efficacy of the ATRA group was better than that of the control group. The mean platelet count at weeks 1, 2, 3, and 4 posttreatment, along with the mean maximum platelet count posttreatment, exhibited higher values in the ATRA group than in the control group; however, these disparities did not reach statistical significance (P=0.310; P=0.568; P=0.779; P=0.618; P=0.355). ATRA was well tolerated, and only one patient developed grade I dry mouth and headache, which improved after dose reduction. There was no difference between the ATRA and control groups in terms of medication adverse effects (13.3% (2/15) vs. 13.3% (2/15), P=1.000). Conclusions: Eltrombopag plus ATRA is an effective and well-tolerated approach for treating steroid-resistant/recurrent ITP. Eltrombopag plus ATRA can enhance patients' complete remission and is well tolerated.

Folic acid supplementation rescues bladder injury in fetal rats with myelomeningocele.

Bladder dysfunction has been linked to the progression of renal failure in children with neurogenic bladder (NB) dysfunction. The purpose of this study was to determine whether bladder injuries in fetal rats with myelomeningocele (MMC) may be treated with folic acid. Pregnant Sprague-Dawley rats were randomly divided into three groups. On the 10th day of gestation, pregnant rats were intragastrically injected with all-trans retinoic acid (ATRA) (60 mg/kg) to induce MMC fetal rats. The same amount of olive oil was put into the control group to create normal fetal rats. The rats in the rescue group were given folic acid (40 mg/kg) by gavage 0.5 and 12 hr after ATRA therapy. Bladders were obtained via cesarean section on embryonic day E20.5 and examined for MMC. The histology of the fetuses was examined using hematoxylin and eosin staining, and immunohistochemistry (IHC) was utilized to determine the expression of α-smooth muscle actin (α-SMA) and neuron-specific nuclear-binding protein (NeuN). Furthermore, the levels of neuromuscular development-related and apoptotic proteins were determined by western blotting. The incidence of MMC in the model group was 60.6% (20/33) while it was much lower in the rescue group (21.4%). In comparison to the model group, the weight and crown-rump length of the fetal rats in the rescue group were significantly improved. IHC revealed that there was no significant difference in the expression of α-SMA and NeuN between the control and ATRA groups, while the expression levels decreased significantly in the MMC group. Western blot analysis showed that there was no significant difference between the model and ATRA groups, but the expression of the α-SMA protein and the β3-tubulin was much lower in the MMC group than in the control group. After the administration of folic acid, the α-SMA and β3-tubulin proteins considerably increased in the folic acid-rescued MMC group and folic acid-rescued ATRA group. Meanwhile, in the control group, the expression of cleaved caspase-3 in the bladder tissue was significantly higher, and the expression of poly (ADP-ribose) polymerase (PARP) protein was significantly lower compared to the control group. Folic acid therapy reduced cleaved caspase-3 expression while increasing PARP expression in comparison to the MMC group. NB in MMC fetal rats is associated with the reduction of bladder nerve and smooth muscle-related protein synthesis. However, folic acid therapy can help improve these functional deficiencies. Folic acid also exhibits strong anti-apoptotic properties against NB in MMC fetal rats.

All-Trans Retinoic Acid Promotes M2 Macrophage Polarization in Vitro by Activating the p38MAPK/STAT6 Signaling Pathway

ABSTRACT Background M2-type macrophages are inflammation-suppressing cells that are differentiated after induction by cytokines such as IL-4 or IL-13, which play an important regulatory role in inflammation and influence the regression of inflammation-related diseases. All-trans retinoic acid (ATRA) has an important role in suppressing immune-mediated inflammatory responses but the effect and underlying mechanism of ATRA on the polarization of M2 macrophages remains unclear. Methods Macrophages were isolated from peritoneal wash fluid, and IL-4 (20 ng/mL) was used to construct a m2-type macrophage polarization model. The model was incubated with different concentrations of ATRA (15 µg/ml, 30 µg/ml, 45 µg/ml) for 24 h, and pretreated macrophages with p38MAPKα inhibitor SB202190 (20 μM). MTT, Trypan blue staining, Annexin V-PE/7-AAD staining, flow cytometry, real-time PCR and western blotting were used to investigate the effect and mechanism of ATRA on the polarization of M2 macrophages. Results Compared with the IL-4 group, the proportion of F4/80+CD206+ M2-type macrophages was significantly higher in the ATRA group (P < 0.01). mRNA and protein expression levels of Arg-1, IL-10 and TGF-β1 were as significantly higher (P < 0.01) in the ATRA group as phosphorylation levels of STAT6 and p38MAPK (P < 0.01). After pretreatment with the addition of the inhibitor SB202190, M2-type macrophages proportion and their associated factors expression were significantly (P < 0.01) reduced, as compared with those in the ATRA group, but they were comparable (P > 0.05) with the IL-4 group. Conclusion The combination of ATRA and IL-4 activated the p38MAPK/STAT6-signaling pathway to promote polarization of M2 macrophages.

Role of Keap1-Nrf2/ARE signal transduction pathway in protection of dexmedetomidine preconditioning against myocardial ischemia/reperfusion injury.

Objective: To explore the role and mechanism of the Kelch sample related protein-1-nuclear factor erythroid-2 related factor 2/antioxidant response element (Keap1-Nrf2/ARE) signaling pathway in protection of dexmedetomidine (DEX) preconditioning against myocardial ischemia/reperfusion injury (MIRI). Methods: A total of 70 male SD rats were randomly divided into seven equal groups (n=10): blank control (S group), ischemia/reperfusion injury (C group), DEX preconditioning (DEX group), tertiary butylhydroquinone (tBHQ) control (tBHQ group), combined tBHQ and DEX preconditioning (tBHQ+DEX group), all-trans retinoic acid (ATRA) control (ATRA group), and combined ATRA and DEX preconditioning (ATRA+DEX group). Serum creatine kinase-MB (CK-MB) and cardiac troponin I (cTnI) concentrations were measured by ELISA kits, and the infarct size (IS) was assessed by Evan’s blue and 2,3,5-triphenyltetrazolium chloride (TTC) staining. Oxidative stress was assessed through Western blotting for expression of Keap1-Nrf2/ARE pathway members and oxidative stress markers. Results: Cardioprotection of DEX, tBHQ, and tBHQ+DEX preconditioning treatments were shown as lower concentrations of serum CK-MB and cTnI and a smaller IS following MIRI in rats compared with those of MIRI rats without pre-treatment. In addition, tBHQ+DEX preconditioning exhibited stronger myocardial protection compared with DEX preconditioning. Mechanistically, the cardioprotection offered by DEX, tBHQ, and tBHQ+DEX preconditioning treatments was mediated via exerting antioxidant stress through activation of the Keap1-Nrf2/ARE signal transduction pathway. Conversely, the protective effects of DEX were diminished by blocking the Keap1-Nrf2/ARE pathway with inhibitor ATRA. Conclusion: DEX preconditioning protects against MIRI by exerting antioxidant stress through activation of the Keap1-Nrf2/ARE signal transduction pathway, while inhibition of the Keap1-Nrf2/ARE signal transduction pathway reverses the protective effect of DEX preconditioning on MIRI.

All-trans retinoic acid increases the pathogenicity of the H9N2 influenza virus in mice

BackgroundThe H9N2 virus can infect not only birds but also humans. The pathogenicity of H9N2 virus infection is determined by an excessive immune response in the lung. All-trans retinoic acid (ATRA), the active metabolite of vitamin A, plays an important regulatory role and has been widely used in the clinical practice. This study was aimed to investigate whether ATRA could regulate the immune response to H9N2 virus infection in the lungs of mice, thereby reducing the pathogenicity of the H9N2 virus in mice.MethodsMice were infected intranasally with H9N2 virus, and injected intraperitoneally with 0.2 mL of ATRA at low (1 mg/kg), medium (5 or 10 mg/kg), or high therapeutic dose (20 mg/kg), and toxic dose (40, 60, or 80 mg/kg), once per day for 10 days. Clinical signs, survival rates, and lung gross pathology were compared between the ATRA-treated H9N2-infected group, the ATRA group, and the H9N2-infected group, to investigate the effect of different doses of ATRA on the pathogenicity of H9N2 virus. Additionally, the viral load and cytokine concentration of lungs were measured at 3, 5, 7, and 9 days after infection, to investigate the potential mechanism of ATRA in affecting the pathogenicity of the H9N2 virus. Expression levels of cellular retinoic acid-binding protein 1 (CRABP1), cellular retinoic acid-binding protein 2 (CRABP2), and Retinoic acid-inducible gene-I (RIG-I) were detected using Western blotting.ResultsThe ATRA-treated H9N2-infected mice showed more severe clinical signs compared with the H9N2-infected group. The medium and high therapeutic doses of ATRA reduced the survival rates, aggravated lung tissue damage, decreased the expression of interferon beta (IFN-β), and increased the concentrations of interleukin-1 beta (IL-1β), tumor necrosis factor alpha (TNF-α), and C-C motif chemokine ligand 2 (CCL2) in the lungs of the H9N2-infected mice. At the same time, the expression patterns of CRABP1, CRABP2, and RIG-I were changed in mice infected by H9N2 and treated with different concentrations of ATRA.ConclusionsOur findings suggest that the therapeutic dose of ATRA can increase the pathogenicity of the H9N2 virus. Therefore, the consequences of those infected by influenza virus would be more severe after ATRA treatment.

Regulatory Effect of All-Trans Retinoic Acid on the Expression of IL-1β in Macrophages and the Mechanisms Involved

To investigate the regulatory effect of all-trans retinoic acid (ATRA) on the expression interleukin-1β (IL-1β) in macrophages and the mechanisms involved. Macrophages were treated with 1 μmol/L ATRA for 24 h before RNA-Sequence. Differentially expressed genes (DEGs) were screened out and analyzed by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, gene ontology (GO) functional analysis, and protein-protein interaction networks (PPI) analysis. After treatment with different doses of ATRA for 24 h, the expression of IL-1β was examined with qRT-PCR and Western blot. The activation of NF-κB signaling and caspase-1 was observed by Western blot and immunofluorescence staining. Compared with the blank control group, a total of 71 DEGs of macrophages were upregulated in the ATRA treatment group. KEGG analysis showed that the up-regulated DEGs were involved in IL-17 signaling pathway, tumor necrosis factor (TNF) signaling pathway, etc. GO analysis indicated that the up-regulated DEGs were involved in the biological processes of the production of IL-1β, response to lipopolysaccharide, etc. PPI analysis revealed that inflammatory cytokines, adhesion molecules, and chemokines were the key genes that ATRA acted on. In vitro experiments showed that ATRA promoted IL-1β expression in macrophages in a concentration-dependent manner. The expression of p-NF-κB, NF-κB, and caspase-1 were significantly increased by ATRA compared with those of the control group ( P<0.05), and p-NF-κB translocated to the cell nucleus in the ATRA group. ATRA may promote the expression of IL-1β by activating NF-κB signaling and caspase-1 in macrophages, this study may provide evidence for the immune regulatory function of ATRA on macrophages.

All-Trans-Retinoic Acid Plus Oxaliplatin/Fluorouracil/Leucovorin for Advanced Hepatocellular Carcinoma with Pulmonary Metastasis: A Multicenter Retrospective Study.

AimTo study the impact of All-trans-retinoic acid (ATRA) plus FOLFOX4 compared to FOLFOX4 alone in patients with advanced hepatocellular carcinoma (HCC) with pulmonary metastasis.MethodsThe data of patients with advanced HCC who underwent systemic chemotherapy using FOLFOX4 or ATRA plus FOLFOX4 at the Eastern Hepatobiliary Surgery Hospital, First Hospital of Jilin University, Zhejiang Sian International Hospital and Fujian Cancer Hospital were retrospectively analyzed. The survival outcomes in the 2 groups were compared.ResultsFrom May 2014 to July 2020, 66 patients were suitable to enter into this study. The median survival (14.0 vs 8.0 months, p=0.012), and the median time to progression in the ATRA plus FOLFOX4 group were both significantly longer than those in the FOLFOX4 group (8.7 vs 3.2 months, p=0.002). The 6 month-, 1 year- and 2 year- overall survival rates were also significantly better in the ATRA plus FOLFOX4 group (100.0%, 64.7% and 20.5%; respectively) than the FOLFOX4 group (59.4%, 21.9%, and 12.5%, respectively; p<0.001). Leukocytopenia, fatigue, anorexia, nausea, were the most common acute toxicities, but these were mostly NCI CTCAE Grade 1 or 2. There was no significant difference in adverse events between the two groups.ConclusionATRA plus FOLFOX4 significantly improved the survival outcomes in patients with advanced HCC with pulmonary metastasis.

All-Trans Retinoic Acid Plus Low-Dose Rituximab Vs Low-Dose Rituximab in Corticosteroid-Resistant or Relapsed ITP

IntroductionApproximately one-third of immune thrombocytopenia (ITP) patients fail to achieve a response with first-line treatments, and most patients who respond to first-line treatment relapse and require further second-line therapies. Rituximab (RTX) has been frequently used in ITP treatment, and proposed schedules include the standard dose (SD) and low dose (LD). Previous studies on LD-RTX in ITP revealed a comparable overall response (OR) and reduced incidences of short- and long-term complications (e.g., infections) compared with SD-RTX (Blood, 2012; Platelets, 2019). However, LD-RTX does not achieve a rapid and long-lasting response in the treatment of ITP. Our preliminary studies demonstrated the efficacy of all-trans retinoic acid (ATRA) in the ITP model due to its effects on inducing megakaryocyte maturation and its immunomodulatory effects (Stem Cells Dev, 2017; J Thromb Haemost, 2017; Br J Haematol, 2018; Haematologica, 2019). Since RTX and ATRA share disparate mechanisms in treating ITP, a combination of RTX and ATRA may work synergistically based on a “double-hit” mechanism targeting both platelet production and destruction, which may overcome the long TTR and improve the SR rate of LD-RTX. Therefore, our study aimed to determine the efficacy and safety of ATRA plus LD-RTX compared to LD-RTX monotherapy in patients with corticosteroid-resistant or relapsed ITP (NCT03304288).MethodsEligible corticosteroid-resistant or relapsed ITP patients with a platelet count < 30 × 10 9/L or bleeding symptoms at enrolment were randomly allocated in a 2:1 ratio to receive 100 mg of RTX weekly for 6 weeks plus ATRA orally at 20 mg/m 2 daily for 12 weeks or 100 mg of RTX weekly for 6 weeks. Stable doses of concomitant corticosteroids, danazol, and cyclosporin were permitted. Treatment was discontinued if platelet counts in two consecutive tests at least 2 weeks apart were more than 300 × 10 9/L and resumed when the platelet count fell to less than 150 × 10 9/L. Assessments were performed at baseline, weekly during the first 4 weeks, every 2 weeks until week 24, and every 4 weeks thereafter. The primary outcome was OR, defined as a platelet count ≥ 30 × 10 9/L, a doubling of the baseline platelet count and the absence of bleeding. Secondary endpoints included sustained response (SR), initial response, complete response, time to response, duration of response and adverse events. SR was defined as maintenance of a platelet count > 30 × 10 9/L, the absence of bleeding, and no requirement for other ITP-specific treatment for 6 consecutive months.ResultsOne hundred sixty-eight patients from 7 tertiary medical centres in China were included between 2017 and 2020, 112 patients received combination treatment of LD-RTX and ATRA, and 56 patients received LD-RTX monotherapy. All the baseline characteristics were comparable between the two groups. The median ages of patients in the LD-RTX plus ATRA group and LD-RTX monotherapy group were 46.0 years and 44.5 years, respectively. For patients in the combination and monotherapy groups, the median number of previous therapies was 2.0. The median baseline platelet count was 17.0 × 10 9/L in the combination group and 19.0 × 10 9/L in the monotherapy group. All the patients were followed up for more than 11 months. OR was observed in 90 (80.4%) patients in the combination group and 33 (58.9%) in the LD-RTX monotherapy group (between-group difference, 0.22; 95% CI, 0.07 to 0.36), indicating that the combination treatment increased the response rate. SR was achieved by 68 (60.7%) patients in the combination group and 23 (41.1%) patients in the monotherapy group at the 6-month follow-up (between-group difference, 0.20; 95% CI, 0.04 to 0.35). Additionally, 56 (50%) subjects in the combination group and 19 (34%) in the monotherapy group were still in sustained remission at 12 months (between-group difference: 0.16; 95% CI, -0.01 to 0.33). No significant difference was found between the 2 treatment groups in terms of the time to a response. The severity of AEs was primarily of grade 1-2. The 2 most common AEs for the combination group were dry skin and headache or dizziness, with incidences of 40.2% (45/112) and 18.8% (21/112), respectively.ConclusionsIn conclusion, ATRA plus LD-RTX significantly increased the overall and sustained response, indicating a novel promising treatment option for corticosteroid-resistant or relapsed adult ITP patients. DisclosuresNo relevant conflicts of interest to declare.

All-trans retinoic acid plus low-dose rituximab vs low-dose rituximab in corticosteroid-resistant or relapsed ITP

AbstractThe study aimed to compare the efficacy and safety of all-trans retinoic acid (ATRA) plus low-dose rituximab (LD-RTX) with LD-RTX monotherapy in corticosteroid-resistant or relapsed immune thrombocytopenia (ITP) patients. Recruited patients were randomized at a ratio of 2:1 into 2 groups: 112 patients received LD-RTX plus ATRA, and 56 patients received LD-RTX monotherapy. Overall response (OR), defined as achieving a platelet count of ≥30 × 109/L confirmed on ≥2 separate occasions (≥7 days apart), at least a doubling of the baseline platelet count without any other ITP-specific treatment, and the absence of bleeding within 1 year after enrollment, was observed in more patients in the LD-RTX plus ATRA group (80%) than in the LD-RTX monotherapy group (59%) (between-group difference, 0.22; 95% CI, 0.07-0.36). Sustained response (SR), defined as maintenance of a platelet count >30 × 109/L, an absence of bleeding, and no requirement for any other ITP-specific treatment for 6 consecutive months after achievement of OR during 1 year following enrollment, was achieved by 68 (61%) patients in the combination group and 23 (41%) patients in the monotherapy group (between-group difference, 0.20; 95% CI, 0.04-0.35). The 2 most common adverse events (AEs) for the combination group were dry skin and headache or dizziness. Our findings demonstrated that ATRA plus LD-RTX significantly increased the overall and sustained response, indicating a promising treatment option for corticosteroid-resistant or relapsed adult ITP. This study is registered at www.clinicaltrials.gov as #NCT03304288.

Impact of preconditioning stem cells with all-trans retinoic acid signaling pathway on cisplatin-induced nephrotoxicity by down-regulation of TGFβ1, IL-6, and caspase-3 and up-regulation of HIF1α and VEGF

The survival reduction after transplantation limited the clinical uses of stem cells so the current study explored preconditioning adipose-derived stem cells (ADMSCs) and all-trans retinoic acid (ATRA) effects on cisplatin that caused acute kidney injury (AKI). One hundred and fifty Sprague–Dawley male rats were distributed into five groups: control group; Cisplatin (CIS) group; CIS and ATRA group; CIS and ADMSC group, and CIS, ATRA, and ADMSCs group. Ten rats were euthanized after 3rd, 7th, and 11th days from CIS injection. Renal function, molecular studies, and histopathological analysis were studied. The preconditioning of ADMSCs with ATRA increased the viability of the cells which was reflected in the amelioration of kidney functions after CIS injection by the significant reduction of serum creatinine, microalbuminuria, as well as NO, and the significant rise of creatinine clearance, as well as SOD compared to the group of cisplatin. ATRA also supported ADMSCs by a significant down-regulation of caspase-3, il-6 and TGFβ1, and a significant up-regulation of HIF1, VEGF and CD31 compared to group of cisplatin which reversed the cisplatin effect. ATRA increased renoprotective properties of ADMSCs against cisplatin- induced AKI by reducing the apoptosis, inflammation, and stimulating angiogenesis.

Cardioprotective effect of all-trans retinoic acid on cisplatin induced cardiotoxicity in rats

used in the treatment of various tumors. Retinoic acid has potent antioxidant effects. In this study, it is aimed to reveal the effects of all-trans retinoic acid (ATRA) on CP induced cardiotoxicity.&#x0D; Materials and Methods: In the study, wistar albino rats were used. Control group received single daily doses of 1 ml/kg saline and ATRA group received single daily doses of ATRA(7,5mg/kg/day) intraperitoneally (i.p.) for 10 days. ATRA+CP group received a single dose of CP(7mg/kg) i.p. on the fourth day of the 10 days of ATRA (7,5mg/kg/day) i.p. treatment. The rats in the CP group received only a single dose of cisplatin(7mg/kg) i.p. given on the 4th of 10 days of treatment. After treatment, the groups were compared based on cardiac histopathology findings.&#x0D; Results: Necrosis, cytoplasmic vacuolization, congestion, hemorrhage and edema were more common in the CP group than the control group). Necrosis and cytoplasmic vacuolization in the all-trans retinoic acid + cisplatin group was observed statistically significantly less frequently than the CP group. &#x0D; Conclusion: This study confirmed that cisplatin therapy had destructive effects on heart tissue, and showed that all-trans retinoic acid treatment could histopathologically prevent cisplatin-induced cardiotoxicity.

All-trans retinoic acid regulating angiopoietins-1 and alleviating extracellular matrix accumulation in interstitial fibrosis rats

All-trans retinoic acid (ATRA) is one of essentially active metabolite of vitamin A, and plays an important role in diverse physiological processes, such as cellular growth and function. Renal interstitial fibrosis (RIF) is a common pathological characteristic of chronic renal disease causing end-stage renal disease currently lacking effective treatment. Low level of Angiopoietins-1 (Angpt-1) is associated with extracellular matrix accumulation and fibrosis diseases. This study was performed to assess the association of ATRA with Angpt-1 in RIF disease. Rats were divided into three groups: group of sham (SHO group), group of unilateral ureteral obstruction group (UUO group), UUO mice administrated daily at the dose of ATRA (ATRA group). Masson-staining was used to detect the histologic lesion. Immunohistochemistry and Western-blot were applied to determine the targeted proteins. RIF score was significantly increased in UUO rats when compared with that of SHO group, and the fibrosis score was notably reduced in ATRA group. Transforming growth factor-β1 (TGF-β1), collagen IV (Col-IV) and fibronectin (FN) expressions in UUO group were significantly up-regulated, whereas Angpt-1 expression was significantly down-regulated compared with the SHO group. ATRA treatment reduced TGF-β1, Col-IV and FN expressions and improved Angpt-1 expression compared with the UUO group. The protein expression of Angpt-1 in kidney tissue of UUO group was negatively correlated with RIF index and protein expressions of Col-IV, FN and TGF-β1. In conclusion, low expression of Angpt-1 was associated with the RIF disease and ATRA treatment can increase the Angpt-1 and alleviate the RIF lesion in UUO rats.

Ling-Gui-Zhu-Gan Decoction Protects H9c2 Cells against H2O2-Induced Oxidative Injury via Regulation of the Nrf2/Keap1/HO-1 Signaling Pathway.

Objectives Ling-Gui-Zhu-Gan decoction (LGZGD) is a potentially effective treatment for heart failure, and it showed significant anti-inflammatory potential in our previous studies. However, its ability to ameliorate heart failure through regulation of oxidative stress response is still unknown. This study was aimed to investigate the protective effect of LGZGD-containing serum on H2O2-induced oxidative injury in H9c2 cells and explore the underlying mechanism. Methods Eighteen rats were randomly divided into two groups: the blank control group and LGZGD group. The LGZGD group rats were administrated with 8.4 g/kg/d LGZGD for seven consecutive days through gavage, while the blank control group rats were given an equal volume of saline. The serum was extracted from all the rats. To investigate the efficacy and the underlying mechanism of LGZGD, we categorized the H9c2 cells into groups: the control group, model group, normal serum control (NSC) group, LGZGD group, LGZGD + all-trans-retinoic acid (ATRA) group, and ATRA group. Malonedialdehyde (MDA) and superoxide dismutase (SOD) were used as markers for oxidative stress. Dichlorodihydrofluorescin diacetate (DCFH-DA) staining was used to measure the levels of reactive oxygen species (ROS). The apoptosis rate was detected using flow cytometry. The expression levels of pro-caspase-3, cleaved-caspase-3, Bcl-2, Bax, Keap1, Nrf2, and HO-1 were measured using western blotting. The mRNA levels of Keap1, Nrf2, and HO-1 were measured using RT-qPCR. Results The LGZGD attenuated injury to H9c2 cells and reduced the apoptosis rate. It was also found to upregulate the SOD activity and suppress the formation of MDA and ROS. The expression levels of pro-caspase-3 and Bcl-2 were significantly increased, while those of cleaved-caspase-3 and Bax were decreased in the LGZGD group compared with the model group. As compared with the model group, the LGZGD group demonstrated decreased Keap1 protein expression and significantly increased Nrf2 nuclear expression and Nrf2-mediated transcriptional activity. ATRA was found to reverse the LGZGD-mediated antioxidative and antiapoptotic effect on injured H9c2 cells induced by H2O2. Conclusion Our results demonstrated that LGZGD attenuated the H2O2-induced injury to H9c2 cells by inhibiting oxidative stress and apoptosis via the Nrf2/Keap1/HO-1 pathway. These observations suggest that LGZGD might prevent and treat heart failure through regulation of the oxidative stress response.

All-trans retinoic acid attenuates the progression of Ang II-induced abdominal aortic aneurysms in ApoE\u2212/\u2212mice

BackgroundTo determine whether all-trans retinoic acid (ATRA) can influence the development of Angiotensin II (Ang II) induced experimental abdominal aortic aneurysms (AAAs).MethodsApolipoprotein E knock-out (ApoE−/−) mice were randomly assigned to 4 groups. Mice in the AAA and ATRA groups underwent continuous subcutaneous Ang II infusion for 28 days to induce AAA, while the Sham and Control groups were infused with saline. Systolic blood pressure was measured by the tail-cuff technique. The Control and ATRA groups received ATRA treatment. Aortic tissue samples were obtained at 28 days after surgery and evaluated by aortic diameter measurement, Western blotting, immunohistochemistry, and hematoxylin-eosin (H&E) and Verhoeff-Van Gieson (EVG) staining.ResultsThe abdominal aortic diameter was significantly reduced in the ATRA group compared with the AAA group (3 of 12 (25%) vs 9 of 12 (75%), P < 0.05), and the ATRA group exhibited reduced blood pressure on days 7, 14, and 28. Low expression of angiotensin II receptor type 1 (AT1), matrix metalloproteinase 2 (MMP2), and matrix metalloproteinase 9 (MMP9) and EVG staining revealed a significant reduction in the disruption of elastic fibers in the abdominal aortic tissue of the ATRA group compared to the AAA group. Western blot analysis indicated that protein levels of retinoic acid receptor α (RARα), MMP2, MMP9, and AT1 were dramatically affected by ATRA treatment.ConclusionsIn conclusion, ATRA attenuates the progression of Ang II-induced AAAs, possibly by downregulating MMP2, MMP9, and AT-1 expression.

RNA-seq analysis of palatal transcriptome changes in all-trans retinoic acid-induced cleft palate of mice

Cleft palate is a common congenital maxillofacial malformation in newborns. All-trans retinoic acid (atRA) is an ideal exogenous stimulus to construct a mouse cleft palate model. However, the precise pathogenic mechanism remains to be elucidated. In our study, to explore the toxicity of atRA on palatal shelves during different stages of palate development, a total of 100 mg/kg atRA was administered to C57BL/6 mice at embryonic day 10.5 (E10.5). Mouse embryonic palatal shelves at E13.5, E14.5, E15.5, and E16.5 were collected for RNA extraction and histological treatment. Changes in gene expression were tested through RNA-seq. Selected differentially expressed genes (DEGs) related to metabolic pathways, such as Ptgds, Ttr, Cyp2g1, Ugt2a1 and Mgst3, were validated and analyzed by Quantitative real-time PCR (qRT-PCR). In addition, Gene Oncology analysis showed that transcriptional changes of genes from extracellular matrix (ECM) components, such as Spp1, and crystallin family might play important role in palatal shelves elevation (E13.5-E14.5). Therefore, the protein expression level of Ttr and Spp1 from E13.5 to E16.5 were tested by immunohistochemistry (IHC). Besides, the mRNA level of Spp1, were down-regulated at E16.5 and the protein were down-regulated at E15.5 and E16.5 in all-trans retinoic acid group, suggesting that atRA may involve in palatal bone formation by regulating Spp1. Overall, gene transcriptional profiles were obviously different at each time point of palate development. Thus, this study summarized some pathways and genes that may be related to palatogenesis and cleft palate through RNA-seq, to provide a direction for subsequent studies on the mechanism and targeted therapy of cleft palate.

All-trans retinoic acid and vascular endothelial growth factor induced the directional osteogenic differentiation of mouse embryonic fibroblasts

To investigate the effect of all-trans retinoic acid (ATRA) and vascular endothelial growth factor (VEGF) on the osteogenic differentiation of mouse embryonic fibroblasts (MEFs). The fetal mice in the uterus of NIH pregnant mice (pregnancy 12-15 days) were collected, and the heads and hearts etc. were removed. Then MEFs were separated from the rest tissues of the fetal mice and cultured by trypsin digestion and adherent culture. HEK-293 cells were used to obtain recombinant adenovirus-red fluorescent protein (Ad-RFP) and Ad-VEGF by repeatedly freezing and thawing. Alkaline phosphatase (ALP) staining and quantitative detection were used to detect the changes of ALP activity in MEFs applied with ATRA or VEGF alone or combined use of ATRA and VEGF on the 3rd and 5th days. The cultured 3rd to 4th generation MEFs were divided into groups A, B, C, and D, and were cultured with DMSO plus Ad-RFP, ATRA, Ad-VEGF, ATRA plus Ad-VEGF, respectively. Real-time fluorescence quantitative PCR (qRT-PCR) was used to detect the mRNA expressions of osteogenic markers including ALP, collagen type Ⅰ, osteopontin (OPN), osteocalcin (OCN), and angiogenic markers including VEGF, angiopoietin 1 (ANGPT1), and endomucin (EMCN) on the 3rd and 7th days. Immunohistochemical staining was used to detect the protein expressions of OPN and VEGF on the 3rd, 5th, and 7th days in each group. Alizarin red staining was used to detect calcium salt deposition levels in each group at 14 and 21 days after osteogenic induction. Fifteen athymic female nude mice aged 4 to 6 weeks were randomly divided into 3 groups and 5 mice in each group. Then MEFs treated with ATRA, Ad-VEGF, and ATRA plus Ad-VEGF were injected subcutaneously into the dorsal and ventral sides, respectively. X-ray observation, gross observation, and histological staining (Masson, HE, and Safranin O-fast green stainings) were performed at 5 weeks after implantation to observe the ectopic bone formation in nude mice in each group. MEFs were successfully isolated and cultured. The acquired Ad-RFP and Ad-VEGF were successfully transfected into MEFs with approximately 50% and 20% transfection rates. ALP activity tests showed that ATRA or Ad-VEGF could enhance ALP activity in MEFs ( P<0.05), and ATRA had a stronger effect than Ad-VEGF; and the combined use of ATRA and Ad-VEGF significantly enhanced the ALP activity in MEFs ( P<0.05). qRT-PCR test showed that the combined use of ATRA and Ad-VEGF also increased the relative mRNA expressions of early-stage osteogenesis-related markers ALP, OPN, and collagen type I ( P<0.05); the relative mRNA expressions of angiogenesis-related markers VEGF, EMCN, and ANGPT1 increased at 7 days ( P<0.05). Immunohistochemical staining showed that ATRA combined with Ad-VEGF not only enhanced OPN protein expression, but also increased VEGF protein expression on 7th day. Alizarin red staining showed that the application of ATRA or Ad-VEGF induced weak calcium salt deposition, and the combined use of ATRA and Ad-VEGF significantly enhanced the effect of calcium salt deposition in MEFs. The results of implantation experiments in nude mice showed that X-ray films observation revealed obvious bone mass in the ATRA plus Ad-VEGF group, and the bone was larger than that in other groups. Histological staining showed a large amount of collagen and mature bone trabeculae, bone matrix formation, and gray-green collagen bone tissue, indicating that the combined use of ATRA and Ad-VEGF significantly enhanced the osteogenic effect of MEFs in vivo. The combined use of ATRA and VEGF can induce the osteogenic differentiation of MEFs.

All-trans retinoic acid reverses malignant biological behavior of hepatocarcinoma cells by regulating miR-200 family members

As a potential chemo-therapeutic agent, all-trans retinoic acid (ATRA) can significantly reverse epithelial-mesenchymal transition (EMT) of hepal-6 hepatocarcinoma cell line in vitro, but the mechanism is unclear. The expression profile of microRNA-200 (miR-200) families is different in hepatocellular carcinoma. In this study, we found that ATRA treatment could up-regulate the expression of miR-200a-3p, 200c-3p, and 141-3p, which were involved in ATRA regulated proliferation and apoptosis of hepal-6 cell, but not colony formation. Meanwhile, miR-200a-3p, 200c-3p, and 141-3p could recovery ATRA inhibited migration and invasion abilities of hepal-6 cells at various levels. miR-200a-3p and 200c-3p prevented ATRA from inducing the differentiation and hepatic functions of hepal-6 cells. Antagomir specific for miR-200a-3p and 200c-3p down-regulated the expression of CK18, but only miR-200a-3p antagomir played prominent role in regulating the expression of these mesenchymal markers, N-Cadherin, Snail and Twist. The transcriptional activities of 8 transcription factors were up-regulated and 35 transcription factors were down-regulated by ATRA. Compared with ATRA group, inhibition of miR-200a-3p, 200c-3p, and 141-3p significantly strengthened the expression of Fra1/Jun (AP1), Ets1/PEA3, Brn3, and Zeb1/AREB6 at varying degrees. Therefore, this result suggested that ATRA may suppress EMT through down-regulating miR-200a-3p, 200c-3p and 141-3p related transcription factors. miR-200 and their downstream genes might be the potentially specific targets for the treatment of hepatocarcinoma.

Effects of ATRA on diabetic rats with renal ischemia-reperfusion injury.

Purpose To explore the role of all-trans retinoic acid (ATRA) in renal ischemia/reperfusion injury of diabetic rats.Methods Sixty adult male rats were randomly divided into 6 groups, including sham group (S group), ischemia-reperfusion group (I/R group), ischemia-reperfusion+ATRA group (A group), diabetic group (D group), diabetic ischemia-reperfusion group (DI/R group), diabetic ischemia-reperfusion +ATRA group (DA group). The levels of creatinine (Cr), cystatin C (Cys-C) and β2-microglobulin (β2-MG) were measured. Morphology of renal tissue was observed under light microscope.Results DJ-1, Nrf2, HO-1 and caspase-3 were detected by western blot. DJ-1, Nrf2, HO-1 and caspase-3 in I/R group, D group and DI/R group was higher than that in S group. Compared with I/R group, Nrf2 and HO-1 in A group was decreased, but caspase-3 was increased. However, Nrf2 in DA group was higher than that in DI/R group, HO-1 and caspase-3 in DA group were lower than that in DI/R group. Compared with group S, Cr, Cys-C and β2-MG in I/R group, A group, D group, and DI/R group were higher. Whereas the levels of Cr, Cys-C, β2-MG and renal injury score in DA group were lower than those in DI/R group.Conclusion ATRA has a protective effect on renal ischemia-reperfusion injury in diabetic rats, maybe relating to DJ/Nrf2 pathway.

All‐trans retinoic acid improves pancreatic cell proliferation on induced type 1 diabetic rats

All-trans retinoic acid (ATRA) has been extensively studied as an integrating component of endocrine functions in the pancreas. The aim of this study was to evaluate the effects of ATRA on physiopathological biomarkers in an experimental model of rat with type 1 diabetes induced by alloxan (T1D). Twenty Wistar rats were divided equally into five groups, each receiving a different treatment: a control group (CG), a diabetic group without T1D treatment, a diabetic group treated with ATRA, a diabetic group supplemented with vitamin E (VIT E), and a group that was given olive oil (V). The administration of ATRA for 17days produced a significant reduction in weight and glucose levels, compared to the T1D and VIT E groups. The evaluation of total antioxidant capacity (TAC) and lipoperoxidation showed no relevant difference among the groups. The results of the histological analysis showed similarities both in the size and in the number of islets of Langerhans in the pancreatic tissue obtained from the ATRA group and the CG. ATRA displayed a significant reduction of glycemic values in diabetic rats. Ultrastructurally, ß-cells, acinar, and ductal cells restored their normal appearance. ATRA can contribute to the recovery of pancreatic damage due to alloxan induction. It seems that the antioxidant effect of ATRA is not responsible for the differences observed.