PPARγ alleviates preeclampsia development by regulating lipid metabolism and ferroptosis.

The study aims to explore the effect of PPARγ signaling on ferroptosis and preeclampsia (PE) development. Serum and placental tissue are collected from healthy subjects and PE patients. The PPARγ and Nrf2 decreases in the PE. Rosiglitazone intervention reverses hypoxia-induced trophoblast ferroptosis and decreases lipid synthesis by regulating Nfr2 and SREBP1. Compared to the Hypoxia group, the migratory and invasive abilities enhance after rosiglitazone and ferr1 treatment. Rosiglitazone reduces the effect of hypoxia and erastin. The si-Nrf2 treatment attenuats the effects of rosiglitazone on proliferation, migration, and invasion. The si-Nrf2 does not affect SREBP1 expression. PPARγ agonists alleviates ferroptosis in the placenta of the PE rats. The study confirms that PPARγ signaling and ferroptosis-related indicators were dysregulated in PE. PPARγ/Nrf2 signaling affects ferroptosis by regulating lipid oxidation rather than SREBP1-mediated lipid synthesis. In conclusion, our study find that PPARγ can alleviate PE development by regulating lipid oxidation and ferroptosis.

PPAR-γ regulates the polarization of M2 macrophages to improve the microenvironment for autologous fat grafting.

The unpredictable survival rate of autologous fat grafting (AFG) seriously affects its clinical application. Improving the survival rate of AFG has become an unresolved issue in plastic surgery. Peroxisome proliferator-activated receptor-γ (PPAR-γ) regulates the adipogenic differentiation of adipocytes, but the functional mechanism in AFG remains unclear. In this study, we established an animal model of AFG and demonstrated the superior therapeutic effect of PPAR-γ regulation in the process of AFG. From day 3 after fat grafting, the PPAR-γ agonist rosiglitazone group consistently showed better adipose integrity, fewer oil cysts, and fibrosis. Massive macrophage infiltration was observed after 7 days. At the same time, M2 macrophages begin to appear. At day 14, M2 macrophages gradually became the dominant cell population, which suppressed inflammation and promoted revascularization and fat regeneration. In addition, transcriptome sequencing showed that the differentially expressed genes in the Rosiglitazone group were associated with the pathways of adipose regeneration, differentiation, and angiogenesis; these results provide new ideas for clinical treatment.

Rosiglitazone alleviates LPS-induced endometritis via suppression of TLR4-mediated NF-κB activation.

OBJECTIVE: The aim of this study was to investigate the anti-inflammatory effect of Rosiglitazone (RGZ) on lipopolysaccharide (LPS) -induced Endometritis and explore its possible mechanism. METHODS: The preventive and therapeutic effects of RGZ on Endometritis were studied in vivo and in vitro. A total of 40 female C57BL/6 mice were randomly divided into the following 4 groups: RGZ+LPS, RGZ control, LPS and DMSO control. The mice uterine tissue sections were performed with HE and immunohistochemical staining. Human endometrial stromal cells (HESCs) were cultured, and different concentrations of LPS stimulation groups and RGZ and/or a TLR4 signaling inhibitor TAK-242 pretreatment +LPS groups were established to further elucidate the underlying mechanisms of this protective effect of RGZ. RESULTS: The HE results in mice showed that RGZ+LPS group had less tissue loss than LPS group. Immunohistochemical staining (IHC) results showed that the expression of TLR4 after RGZ treatment was significantly lower than that in LPS group. These findings suggested that RGZ effectively improves the pathological changes associated with LPS-induced endometritis by inhibiting TLR4. Reverse transcription-polymerase chain reaction and western blot analysis demonstrated that RGZ pretreatment suppresses the expression of Toll-like receptor 4 (TLR4) and its downstream activation of nuclear factor-κB (NF-κB). In vitro, RGZ inhibited LPS-stimulated expression of proinflammatory cytokines in a dose-dependent manner and also downregulated LPS induced toll-like receptor 4 (TLR4) expression and inhibited phosphorylation of LPS-induced nuclear transcription factor-kappa B (NF-κB) P65 protein. CONCLUSIONS: These results suggest that RGZ may inhibit LPS-induced endometritis through the TLR4-mediated NF-κB pathway.

BDE-99 stimulates generation of aberrant brown/beige adipocytes.

Adipose tissue compromises one of the principal depots where brominated flame retardants (BFR) accumulate in vivo, yet whether BFR disturb thermogenic brown/beige adipocytes is still not referred to date. Herein, effects of BDE-99, a major congener of polybrominated diphenyl ethers (PBDEs) detected in humans, on brown/beige adipocytes were explored for the first time, aiming to provide new knowledge evaluating the obesogenic and metabolic disrupting effects of BFR. Our results firstly demonstrated that exposure to BDE-99 during the lineage commitment period significantly promoted C3H10T1/2 MSCs differentiating into brown/beige adipocytes, evidenced by the increase of brown/beige adipocyte marker UCP1, Cidea as well as mitochondrial membrane potential and basal respiration rate, which was similar to pharmacological PPARγ agonist rosiglitazone. Unexpectedly, the mitochondrial maximal respiration rate of BDE-99 stimulated brown/beige adipocytes was not synchronously enhanced and resulted in a significant reduction of mitochondrial spare respiration capacity (SRC) compared to control or rosiglitazone stimulated adipocytes, indicating a deficient energy-dissipating capacity of BDE-99 stimulated thermogenic adipocytes. Consistently with compromised mitochondrial SRC, lipidomic analysis further revealed that the lipids profile of mitochondria derived from BDE-99 stimulated brown/beige adipocytes were quite different from control or rosiglitazone stimulated cells. In detail, BDE-99 group contains more free fatty acid (FFA) and lyso-PE in mitochondria. In addition to energy metabolism, our results also demonstrated that BDE-99 stimulated brown/beige adipocytes were deficient in endocrine, which secreted more adverse adipokine named resistin, coinciding with comparable beneficial adipokine adiponectin compared with that of rosiglitazone. Taken together, our results showed for the first time that BDE-99 stimulated brown/beige adipocytes were aberrant in energy metabolism and endocrine, which strongly suggests that BDE-99 accumulated in human adipose tissue could interfere with brown/beige adipocytes to contribute to the occurrence of obesity and relevant metabolic disorders.

Rosiglitazone regulates astrocyte polarization and neuroinflammation in a PPAR-γ dependent manner after experimental traumatic brain injury.

BACKGROUND: Traumatic brain injury (TBI) is a leading cause of high mortality and disability worldwide. Overactivation of astrocytes and overexpression of inflammatory responses in the injured brain are characteristic pathological features of TBI. Rosiglitazone (ROS) is a peroxisome proliferator-activated receptor-γ (PPAR-γ) agonist known for its anti-inflammatory activity. However, the relationship between the inflammatory response involved in ROS treatment and astrocyte A1 polarization remains unclear. OBJECTIVE: This study aimed to investigate whether ROS treatment improves dysfunction and astrocyte A1 polarization induced after TBI and to elucidate the underlying mechanisms of these functions. METHODS: SD rats were randomly divided into sham operation group, TBI group, TBI+ROS group, and TBI+ PPAR-γ antagonist group (GW9662 + TBI). The rat TBI injury model was prepared by the CCI method; brain water content test and wire grip test scores suggested the prognosis; FJB staining showed the changes of ROS on the morphology and number of neurons in the peripheral area of cortical injury; ELISA, immunofluorescence staining, and western blotting analysis revealed the effects of ROS on inflammatory response and astrocyte activation with the degree of A1 polarization after TBI. RESULTS: Brain water content, inflammatory factor expression, and astrocyte activation in the TBI group were higher than those in the sham-operated group (P < 0.05); compared with the TBI group, the expression of the above indexes in the ROS group was significantly lower (P < 0.05). Compared with the TBI group, PPAR-γ content was significantly higher and C3 content was considerably lower in the ROS group (P < 0.05); compared with the TBI group, PPAR-γ content was significantly lower and C3 content was substantially higher in the inhibitor group (P < 0.05). CONCLUSION: ROS can exert neuroprotective effects by inhibiting astrocyte A1 polarization through the PPAR-γ pathway based on the reduction of inflammatory factors and astrocyte activation in the brain after TBI.

Abrus precatorius Leaf Extract Stimulates Insulin-mediated Muscle Glucose Uptake: In vitro Studies and Phytochemical Analysis.

Diabetes mellitus, linked with insulin resistance and hyperglycaemia, is a leading cause of mortality. Glucose uptake through glucose transporter type 4, especially in skeletal muscle, is crucial for maintaining euglycaemia and is a key pathway targeted by antidiabetic medication. Abrus precatorius is a medicinal plant with demonstrated antihyperglycaemic activity in animal models, but its mechanisms are unclear.This study evaluated the effect of a 50% ethanolic (v/v) A. precatorius leaf extract on (1) insulin-stimulated glucose uptake and (2) related gene expression in differentiated C2C12 myotubes using rosiglitazone as a positive control, and (3) generated a comprehensive phytochemical profile of A. precatorius leaf extract using liquid chromatography-high resolution mass spectrometry to elucidate its antidiabetic compounds. A. precatorius leaf extract significantly increased insulin-stimulated glucose uptake, and insulin receptor substrate 1 and Akt substrate of 160 kDa gene expression; however, it had no effect on glucose transporter type 4 gene expression. At 250 µg/mL A. precatorius leaf extract, the increase in glucose uptake was significantly higher than 1 µM rosiglitazone. Fifty-five phytochemicals (primarily polyphenols, triterpenoids, saponins, and alkaloids) were putatively identified, including 24 that have not previously been reported from A. precatorius leaves. Abrusin, precatorin I, glycyrrhizin, hemiphloin, isohemiphloin, hispidulin 4'-O-ß-D-glucopyranoside, homoplantaginin, and cirsimaritin were putatively identified as known major compounds previously reported from A. precatorius leaf extract. A. precatorius leaves contain antidiabetic phytochemicals and enhance insulin-stimulated glucose uptake in myotubes via the protein kinase B/phosphoinositide 3-kinase pathway by regulating insulin receptor substrate 1 and Akt substrate of 160 kDa gene expression. Therefore, A. precatorius leaves may improve skeletal muscle insulin sensitivity and hyperglycaemia. Additionally, it is a valuable source of bioactive phytochemicals with potential therapeutic use for diabetes.

Harnessing peroxisome proliferator-activated receptor γ agonists to induce Heme Oxygenase-1: a promising approach for pulmonary inflammatory disorders.

The activation of peroxisome proliferator-activated receptor (PPAR)-γ has been extensively shown to attenuate inflammatory responses in conditions such as asthma, acute lung injury, and acute respiratory distress syndrome, as demonstrated in animal studies. However, the precise molecular mechanisms underlying these inhibitory effects remain largely unknown. The upregulation of heme oxygenase-1 (HO-1) has been shown to confer protective effects, including antioxidant, antiapoptotic, and immunomodulatory effects in vitro and in vivo. PPARγ is highly expressed not only in adipose tissues but also in various other tissues, including the pulmonary system. Thiazolidinediones (TZDs) are highly selective agonists for PPARγ and are used as antihyperglycemic medications. These observations suggest that PPARγ agonists could modulate metabolism and inflammation. Several studies have indicated that PPARγ agonists may serve as potential therapeutic candidates in inflammation-related diseases by upregulating HO-1, which in turn modulates inflammatory responses. In the respiratory system, exposure to external insults triggers the expression of inflammatory molecules, such as cytokines, chemokines, adhesion molecules, matrix metalloproteinases, and reactive oxygen species, leading to the development of pulmonary inflammatory diseases. Previous studies have demonstrated that the upregulation of HO-1 protects tissues and cells from external insults, indicating that the induction of HO-1 by PPARγ agonists could exert protective effects by inhibiting inflammatory signaling pathways and attenuating the development of pulmonary inflammatory diseases. However, the mechanisms underlying TZD-induced HO-1 expression are not well understood. This review aimed to elucidate the molecular mechanisms through which PPARγ agonists induce the expression of HO-1 and explore how they protect against inflammatory and oxidative responses.

Metabolic and structural remodeling during browning of primary human adipocytes derived from omental and subcutaneous depots.

OBJECTIVE: This study investigated remodeling of cellular metabolism and structures during browning of primary human adipocytes derived from both visceral and subcutaneous adipose tissues. Effects of glucocorticoids on the browning were also assessed. METHODS: Differentiated omental and subcutaneous human adipocytes were treated with rosiglitazone, with or without dexamethasone, and expression levels of brite adipocyte markers, lipolysis, and lipid droplet and mitochondrial structures were examined. RESULTS: Both omental and subcutaneous adipocytes acquired brite phenotypes upon peroxisome proliferator-activated receptor-γ agonist treatment, and dexamethasone tended to enhance the remodeling. Although rosiglitazone increased lipolysis during treatment, brite adipocytes exhibited lower basal lipolytic rates and enhanced responses to ß-adrenergic agonists or atrial natriuretic peptide. Transcriptome analysis identified induction of both breakdown and biosynthesis of lipids in brite adipocytes. After 60+ days in culture, lipid droplet size increased to ~50 microns, becoming almost unilocular in control adipocytes, and after browning, they acquired paucilocular morphology, clusters of small lipid droplets (1-2 micron) surrounded by mitochondria appearing on the periphery of the central large one. CONCLUSIONS: Metabolic and structural remodeling during browning of primary human adipocytes is similar to previous findings in human adipocytes in vivo, supporting their uses for mechanical studies investigating browning with translational relevance.

Decellularization-Based Modification Strategy for Bioactive Xenografts Promoting Tendon Repair.

Xenografts have emerged as a promising option for severe tendon defects treatment. However, despite undergoing decellularization, concerns still remain regarding the immunogenicity of xenografts. Because certain components within the extracellular matrix also possess immunogenicity. In this study, a novel strategy of post-decellularization modification aimed at preserving the endogenous capacity of cells on collagen synthesis to mask antigenic epitopes in extracellular matrix is proposed. To implement this strategy, a human-derived rosiglitazone-loaded decellularized extracellular matrix (R-dECM) is developed. R-dECM can release rosiglitazone for over 7 days in vitro. By suppressing M1 macrophage polarization, R-dECM protects the migration and collagen synthesis abilities of tendon-derived stem cells (TDSCs), while also stabilizing the phenotype of M2 macrophages in vitro. RNA sequencing reveals R-dECM can mitigate the detrimental crosstalk between TDSCs and inflammatory cells. When applied to a rat patellar tendon defect model, R-dECM effectively inhibits early inflammation, preventing chronic inflammation. Its duration of function far exceeds the release time of rosiglitazone, implying the establishment of immune evasion, confirming the effectiveness of the proposed strategy. And R-dECM demonstrates superior tendon repair outcomes compared to dECM. Thus, this study provides a novel bioactive scaffold with the potential to enhance the long-term clinical outcomes of xenogeneic tendon grafts.

Essential oil from Fructus Alpiniae zerumbet ameliorates vascular endothelial cell senescence in diabetes by regulating PPAR-γ signalling: A 4D label-free quantitative proteomics and network pharmacology study.

ETHNOPHARMACOLOGICAL RELEVANCE: Vascular endothelial cell senescence is associated with cardiovascular complications in diabetes. Essential oil from Fructus Alpiniae zerumbet (Pers.) B.L.Burtt & R.M.Sm. (EOFAZ) has potentially beneficial and promising diabetes-related vascular endothelial cell senescence-mitigating effects; however, the underlying molecular mechanisms remain unclear. AIM OF THE STUDY: To investigate the molecular effects of EOFAZ on vascular endothelial cell senescence in diabetes. MATERIALS AND METHODS: A diabetes mouse model was developed using a high-fat and high-glucose diet (HFD) combined with intraperitoneal injection of low-dose streptozotocin (STZ, 30 mg/kg) and oral treatment with EOFAZ. 4D label-free quantitative proteomics, network pharmacology, and molecular docking techniques were employed to explore the molecular mechanisms via which EOFAZ alleviates diabetes-related vascular endothelial cell senescence. A human aortic endothelial cells (HAECs) senescence model was developed using high palmitic acid and high glucose (PA/HG) concentrations in vitro. Western blotting, immunofluorescence, SA-ß-galactosidase staining, cell cycle, reactive oxygen species (ROS), cell migration, and enzyme linked immunosorbent assays were performed to determine the protective role of EOFAZ against vascular endothelial cell senescence in diabetes. Moreover, the PPAR-γ agonist rosiglitazone, inhibitor GW9662, and siRNA were used to verify the underlying mechanism by which EOFAZ combats vascular endothelial cell senescence in diabetes. RESULTS: EOFAZ treatment ameliorated abnormal lipid metabolism, vascular histopathological damage, and vascular endothelial aging in diabetic mice. Proteomics and network pharmacology analysis revealed that the differentially expressed proteins (DEPs) and drug-disease targets were associated with the peroxisome proliferator-activated receptor gamma (PPAR-γ) signalling pathway, a key player in vascular endothelial cell senescence. Molecular docking indicated that the small-molecule compounds in EOFAZ had a high affinity for the PPAR-γ protein. Western blotting and immunofluorescence analyses confirmed the significance of DEPs and the involvement of the PPAR-γ signalling pathway. In vitro, EOFAZ and rosiglitazone treatment reversed the effects of PA/HG on the number of senescent endothelial cells, expression of senescence-related proteins, the proportion of cells in the G0/G1 phase, ROS levels, cell migration rate, and expression of pro-inflammatory factors. The protective effects of EOFAZ against vascular endothelial cell senescence in diabetes were aborted following treatment with GW9662 or PPAR-γ siRNA. CONCLUSIONS: EOFAZ ameliorates vascular endothelial cell senescence in diabetes by activating PPAR-γ signalling. The results of the present study highlight the potential beneficial and promising therapeutic effects of EOFAZ and provide a basis for its clinical application in diabetes-related vascular endothelial cell senescence.

Head-to-head comparison of BAM15, semaglutide, rosiglitazone, NEN, and calorie restriction on metabolic physiology in female db/db mice.

Metabolic disorders such as type 2 diabetes, fatty liver disease, hyperlipidemia, and obesity commonly co-occur but clinical treatment options do not effectively target all disorders. Calorie restriction, semaglutide, rosiglitazone, and mitochondrial uncouplers have all demonstrated efficacy against one or more obesity-related metabolic disorders, but it currently remains unclear which therapeutic strategy best targets the combination of hyperglycaemia, liver fat, hypertriglyceridemia, and adiposity. Herein we performed a head-to-head comparison of 5 treatment interventions in the female db/db mouse model of severe metabolic disease. Treatments included ∼60 % calorie restriction (CR), semaglutide, rosiglitazone, BAM15, and niclosamide ethanolamine (NEN). Results showed that BAM15 and CR improved body weight and liver steatosis to levels superior to semaglutide, NEN, and rosiglitazone, while BAM15, semaglutide, and rosiglitazone improved glucose tolerance better than CR and NEN. BAM15, CR, semaglutide, and rosiglitazone all had efficacy against hypertriglyceridaemia. These data provide a comprehensive head-to-head comparison of several key treatment strategies for metabolic disease and highlight the efficacy of mitochondrial uncoupling to correct multiple facets of the metabolic disease milieu in female db/db mice.

PPARγ agonist treatment reduces fibroadipose tissue in secondary lymphedema by exhausting fibroadipogenic PDGFRα+ mesenchymal cells.

Secondary lymphedema occurs in up to 20% of patients after lymphadenectomy performed for the surgical management of tumors involving the breast, prostate, uterus, and skin. Patients develop progressive edema of the affected extremity due to retention of protein-rich lymphatic fluid. Despite compression therapy, patients progress to chronic lymphedema in which noncompressible fibrosis and adipose tissue are deposited within the extremity. The presence of fibrosis led to our hypothesis that rosiglitazone, a PPARγ agonist that inhibits fibrosis, would reduce fibrosis in a mouse model of secondary lymphedema after hind limb lymphadenectomy. In vivo, rosiglitazone reduced fibrosis in the hind limb after lymphadenectomy. Our findings verified that rosiglitazone reestablished the adipogenic features of TGF-ß1-treated mesenchymal cells in vitro. Despite this, rosiglitazone led to a reduction in adipose tissue deposition. Single-cell RNA-Seq data obtained from human tissues and flow cytometric and histological evaluation of mouse tissues demonstrated increased presence of PDGFRα+ cells in lymphedema; human tissue analysis verified these cells have the capacity for adipogenic and fibrogenic differentiation. Upon treatment with rosiglitazone, we noted a reduction in the overall quantity of PDGFRα+ cells and LipidTOX+ cells. Our findings provide a framework for treating secondary lymphedema as a condition of fibrosis and adipose tissue deposition, both of which, paradoxically, can be prevented with a pro-adipogenic agent.

Isolation and Culture of Human Meibomian Gland Ductal Cells.

Purpose: Hyperkeratinization of meibomian gland (MG) ducts is currently recognized as the primary pathologic mechanism of meibomian gland dysfunction (MGD). This research figured out a method to isolate the MG ducts and established a novel system to culture the human meibomian gland ductal cells (HMGDCs) for investigating the process of MGD. Methods: The MG ducts were obtained from the eyelids of recently deceased donors and subjected to enzymatic digestion. The acini were then removed to isolate independent ducts. These MG ducts were subsequently cultivated on Matrigel-coated wells and covered with a glass plate to obtain HMGDCs. The HMGDCs were further cultivated until passage 2, and when they reached 60% confluence, they were treated with IL-1ß and rosiglitazone for a duration of 48 hours. Immunofluorescence staining and Western blot techniques were employed to identify ductal cells and analyze the effects of IL-1ß on HMGDCs in an in vitro setting. Results: Ophthalmic micro-forceps and insulin needles can be employed for the purpose of isolating ducts. Within this particular culture system, the rapid expansion of HMGDCs occurred in close proximity to the duct tissue. MG ducts specifically expressed keratin 6 (Krt6) and hardly synthesized lipids. Furthermore, the expression of Krt6 was significantly higher (P < 0.0001) in HMGDCs compared to human meibomian gland cells. Upon treatment with IL-1ß, HMGDCs exhibited an overexpression of keratin 1, which was effectively blocked by the administration of rosiglitazone. Conclusions: The present study successfully isolated human MG ducts and cultured HMGDCs, providing a valuable in vitro model for investigating the mechanism of MGD. Additionally, the potential therapeutic efficacy of rosiglitazone in treating hyperkeratinization of ducts in patients with MGD was identified.

Capsiate-Rich Fraction of Capsicum annuum Induces Muscular Glucose Uptake, Ameliorates Rosiglitazone-Induced Adipogenesis, and Exhibits Activation of NRs Regulating Multiple Signaling Pathways.

Capsiate is a key ingredient in the fruits of a nonpungent cultivar of Capsicum annuum. We investigated the effects of a C. annuum extract (CE) and a capsiate-rich fraction of CE (CR) on nuclear receptors involved in multiple signaling pathways, glucose uptake, and adipogenesis in comparison to pure capsiate (Ca). Similar to the effect of Ca (100 µM), CE (500 µg/mL) and CR (100 µg/mL) caused the activation of PPARα and PPARγ (>3-fold), while CR also activated LXR and NRF2 (>2 fold). CR (200 µg/mL) and Ca (100 µM) decreased lipid accumulation (22.6 ± 14.1 and 49.7 ± 7.3%, respectively) in adipocytes and increased glucose uptake (44.7 ± 6.2 and 30.1 ± 12.2%, respectively) in muscle cells and inhibited the adipogenic effect induced by rosiglitazone by 41.2 ± 5.6 and 13.9 ± 4.3%, respectively. This is the first report to reveal the agonistic action of CR and Ca on multiple nuclear receptors along with their enhanced glucose uptake and antiadipogenic effects. The results indicate the potential utility of the capsiate-rich fraction of C. annuum in alleviating the symptoms of metabolic syndrome and in preventing the undesired adipogenic effects of full PPARγ agonists such as rosiglitazone.

Synthesis, molecular docking, and in vivo antidiabetic evaluation of new benzylidene-2,4-thiazolidinediones as partial PPAR-γ agonists.

Peroxisome proliferator-activated receptor-γ (PPAR-γ) partial agonists or antagonists, also termed as selective PPAR-γ modulators, are more beneficial than full agonists because they can avoid the adverse effects associated with PPAR-γ full agonists, such as weight gain and congestive heart disorders, while retaining the antidiabetic efficiency. In this study, we designed and synthesized new benzylidene-thiazolidine-2,4-diones while keeping the acidic thiazolidinedione (TZD) ring at the center, which is in contrast with the typical pharmacophore of PPAR-γ agonists. Five compounds (5a-e) were designed and synthesized in moderate to good yields and were characterized using spectral techniques. The in vivo antidiabetic efficacy of the synthesized compounds was assessed on streptozotocin-induced diabetic mice using standard protocols, and their effect on weight gain was also studied. Molecular docking and molecular dynamics (MD) simulation studies were performed to investigate the binding interactions of the title compounds with the PPAR-γ receptor and to establish their binding mechanism. Antidiabetic activity results revealed that compounds 5d and 5e possess promising antidiabetic activity comparable with the standard drug rosiglitazone. No compound showed considerable effect on the body weight of animals after 21 days of administration, and the findings showed statistical difference (p < 0.05 to p < 0.0001) among the diabetic control and standard drug rosiglitazone groups. In molecular docking study, compounds 5c and 5d exhibited higher binding energies (- 10.1 and - 10.0 kcal/mol, respectively) than the native ligand, non-thiazolidinedione PPAR-γ partial agonist (nTZDpa) (- 9.8 kcal/mol). MD simulation further authenticated the stability of compound 5c-PPAR-γ complex over the 150 ns duration. The RMSD, RMSF, rGyr, SASA, and binding interactions of compound 5c-PPAR-γ complex were comparable to those of native ligand nTZDpa-PPAR-γ complex, suggesting that the title compounds have the potential to be developed as partial PPAR-γ agonists.

Inhibitory effect and mechanism of Rosiglitazone on M1 type polarization of central microglia in intracerebral hemorrhage mice based on JNK/STAT3 signaling pathway.

BACKGROUND: Intracerebral hemorrhage (ICH) seriously threatens the health of people. In addition, microglia M1 polarization was confirmed to be involved in the progression of ICH. Rosiglitazone was able to be used as an antidiabetic agent, which could activate PPAR-γ, and PPAR-γ was reported to inhibit inflammation in microglia. However, the detailed function of Rosiglitazone in ICH remains unclear. METHODS: In vivo and in vitro experiments were used to test the function of Rosiglitazone in ICH. In addition, RT-qPCR and western blot were performed to evaluate the mRNA and protein level of PPAR-γ, respectively. Immunofluorescence staining was performed to detect the levels of CD206 and CD86, and ELISA was used to measure the levels of pro-inflammatory cytokines. RESULTS: PPAR-γ was downregulated in ICH mice, whereas p-JNK and p-STAT3 were upregulated. Thrombin notably downregulated the level of PPAR-γ in BV2 cells, whereas Rosiglitazone partially reversed this phenomenon. In addition, Rosiglitazone markedly reversed thrombin-induced microglia M1 polarization. Consistently, thrombin-induced inflammatory response in BV2 cells was abolished in the presence of Rosiglitazone. SP600125 (JNK/STAT3 inhibitor) greatly reversed thrombin-induced M1 polarization in microglia, and GW9662 abolished the effect of SP600125. Meanwhile, Rosiglitazone could inactivate JNK/STAT3 pathway through the upregulation of PPAR-γ. Furthermore, Rosiglitazone notably alleviated the symptom of ICH in vivo through inhibiting the apoptosis and mediating PPAR-γ/JNK/STAT3 axis. CONCLUSION: Rosiglitazone could attenuate the inflammation in ICH through inhibiting microglia M1 polarization. Thus, our research would shed now lights on exploring new therapeutic strategies against ICH.

Gene Expression Analyses in Models of Rosiglitazone-Induced Physiological and Pathological Mineralization Identify Novel Targets to Improve Bone and Vascular Health.

Clinical studies revealed detrimental skeletal and vascular effects of the insulin sensitizer rosiglitazone. We have shown earlier that rosiglitazone accelerates osteoblast differentiation from human mesenchymal stem cells (hMSC) at the expense of increased oxidative stress and cell death. In calcifying human vascular cells, rosiglitazone stimulates pathological mineralization, an effect diminished by the antioxidant resveratrol. Here, we aimed to elucidate transcriptional networks underlying the rosiglitazone-enhanced mineralization phenotype. We performed genome-wide transcriptional profiling of osteogenic hMSCs treated with rosiglitazone for short-term periods of 1 up to 48 h during the first two days of differentiation, a phase that we show is sufficient for rosiglitazone stimulation of mineralization. Microarray-based mRNA expression analysis revealed 190 probes that were differently expressed in at least one condition compared to vehicle-treated control. This rosiglitazone gene signature contained well-known primary PPAR targets and was also endogenously regulated during osteogenic hMSC differentiation and osteoblast-like differentiation of vascular smooth muscle cells (VSMCs) into calcifying vascular cells (CVCs). Comparative analysis revealed rosiglitazone targets that were commonly enriched in osteoblasts and CVCs or specifically enriched in either osteoblasts or CVCs. Finally, we compared expression patterns of CVC-specific genes with patient expression data from carotid plaque versus intact adjacent tissue, and identified five rosiglitazone targets to be differentially regulated in CVCs and carotid plaque but not osteoblasts when compared to their non-mineralizing counterparts. These targets, i.e., PDK4, SDC4, SPRY4, TCF4 and DACT1, may specifically control extracellular matrix mineralization in vascular cells, and hence provide target candidates for further investigations to improve vascular health.

Loss of PPARγ activity characterizes early protumorigenic stromal reprogramming and dictates the therapeutic window of opportunity.

Although robustly expressed in the disease-free (DF) breast stroma, CD36 is consistently absent from the stroma surrounding invasive breast cancers (IBCs). In this study, we primarily observed CD36 expression in adipocytes and intralobular capillaries within the DF breast. Larger vessels concentrated in interlobular regions lacked CD36 and were instead marked by the expression of CD31. When evaluated in perilesional capillaries surrounding ductal carcinoma in situ, a nonobligate IBC precursor, CD36 loss was more commonly observed in lesions associated with subsequent IBC. Peroxisome proliferator-activated receptor γ (PPARγ) governs the expression of CD36 and genes involved in differentiation, metabolism, angiogenesis, and inflammation. Coincident with CD36 loss, we observed a dramatic suppression of PPARγ and its target genes in capillary endothelial cells (ECs) and pericytes, which typically surround and support the stability of the capillary endothelium. Factors present in conditioned media from malignant cells repressed PPARγ and its target genes not only in cultured ECs and pericytes but also in adipocytes, which require PPARγ for proper differentiation. In addition, we identified a role for PPARγ in opposing the transition of pericytes toward a tumor-supportive myofibroblast phenotype. In mouse xenograft models, early intervention with rosiglitazone, a PPARγ agonist, demonstrated significant antitumor effects; however, following the development of a palpable tumor, the antitumor effects of rosiglitazone were negated by the repression of PPARγ in the mouse stroma. In summary, PPARγ activity in healthy tissues places several stromal cell types in an antitumorigenic state, directly inhibiting EC proliferation, maintaining adipocyte differentiation, and suppressing the transition of pericytes into tumor-supportive myofibroblasts.

Rosiglitazone inhibits acyl-CoA synthetase long-chain family number 4 and improves secondary brain injury in a rat model of surgical brain injury.

Ferroptosis is a recently discovered non-apoptotic form of cellular death. Acyl-CoA synthetase long-chain family number 4 (ACSL4) is necessary for iron-dependent cellular death, and reactive oxygen species (ROS) produced by ACSL4 are the executioners of ferroptosis. Rosiglitazone improves ferroptosis by inhibiting ACSL4. There is no research indicating whether ACSL4 plays a role in cell death after surgical brain injury (SBI). This study aimed to investigate the role of ACSL4 in SBI via the ferroptosis pathway. Ninety male Sprague-Dawley rats were examined using a model of SBI. Subsequently, the inhibitory effect of rosiglitazone on ACSL4 was assessed via western blot, real-time polymerase chain reaction (PCR), immunofluorescence, fluoro-jade C staining, Perl's staining, ROS assay, and neurological scoring. The results showed that compared with the Sham group, the protein levels of ACSL4 and transferrin were significantly increased after SBI. Administration of rosiglitazone significantly reduced neuronal necrosis, iron deposition, brain water content and ROS in brain tissue and ameliorated neurological deficits at 48 h after SBI, which was concomitant with decreased transferrin expression. These findings demonstrate that SBI-induced upregulation of ACSL4 may be partly mediated by the ferroptosis pathway, which can be reversed by rosiglitazone administration.

Rosiglitazone-Mediated Activation of PPARγ Restores HO1 Expression in the Human Preeclamptic Placenta.

BACKGROUND: Preeclampsia is a hypertensive disorder of pregnancy characterized by chronic placental ischemia and suppression of proangiogenic proteins, causing oxidative stress, hypertension, and maternal systemic organ damage. The transcription factor, PPARγ (peroxisome proliferator-activated receptor-γ) promotes healthy trophoblast differentiation but is dysregulated in the preeclampsia placenta. Our study identifies the beneficial impact of Rosiglitazone-mediated PPARγ-activation in the stressed preeclampsia placenta. METHODS: We used first trimester placentas, preeclamptic and preterm control placentas, and human trophoblast cell lines to study PPARγ activation. RESULTS: Induction of PPARγ activates cell growth and antioxidative stress pathways, including the gene, heme oxygenase 1 (Hmox1). Protein expression of both PPARγ and HO1 (heme oxygenase 1) are reduced in preeclamptic placentas, but Rosiglitazone restores HO1 signaling in a PPARγ-dependent manner. CONCLUSIONS: Restoring disrupted pathways by PPARγ in preeclampsia offers a potential therapeutic pathway to reverse placental damage, extending pregnancy duration, and reduce maternal sequelae. Future research should aim to understand the full scope of impaired PPARγ signaling in the human placenta and focus on compounds for safe use during pregnancy to prevent severe perinatal morbidity and mortality.