Curcumin protects murine lung mesenchymal stem cells from H2O2 by modulating the Akt/Nrf2/HO-1 pathway

Andrographolide induced heme oxygenase-1 expression in MSC-like cells isolated from rat bone marrow exposed to environmental stress

BACKGROUND AND OBJECTIVES

Mesenchymal stem cells (MSC-like cells) are the most important stem cells that are used in transplantation clinically in various applications. The survival rate of MSC-like cells is strongly reduced due to adverse conditions in the microenvironment of transplantation, including environmental stress. Heme oxygenase-1 (HO-1) is a member of the heat shock protein, as well as a stress-induced enzyme, present throughout the body. The present study was conducted to investigate the effect of andrographolide, an active derivative from andrographolide paniculate, on HO-1 expression in mesenchymal stem cells derived from rat bone marrow.

MATERIALS AND METHODS

The rat bone marrow-derived mesenchymal stem cells (BMSC-like cells) were extracted and proliferated in several passages. The identity of MSC-like cells was confirmed by morphological observations and differential tests. The flow cytometry method was used to verify the MSC-specific markers. Isolated MSC-like cells were treated with different concentrations of andrographolide and then exposed to environmental stress. Cell viability was assessed using the MTT colorimetric assay. A real-time PCR technique was employed to evaluate the expression level of HO-1 in the treated MSC-like cells.

RESULTS

Isolated MSC-like cells demonstrated fibroblast-like morphology. These cells in different culture mediums differentiated into osteocytes and adipocytes and were identified using alizarin red and oil red staining, respectively. As well, MSC-like cells were verified by the detection of CD105 surface antigen and the absence of CD14 and CD45 antigens. The results of the MTT assay showed that the pre-treatment of MSC-like cells with andrographolide concentration independently increased the viability and resistance of these cells to environmental stress caused by hydrogen peroxide and serum deprivation (SD). Real-time PCR findings indicated a significant increase in HO-1 gene expression in the andrographolide-receiving groups (p < 0.01).

CONCLUSION

Our results suggest that andrographolide creates a promising strategy for enhancing the quality of cell therapy by increasing the resistance of MSC-like cells to environmental stress and inducing the expression of HO-1.

Antiviral and immunoregulatory effects of curcumin on coxsackievirus B3-infected hepatitis

Fulminant hepatitis is a life-threatening complication of coxsackievirus B (CVB) 3 infections. The condition may deteriorate to disseminated intravascular coagulopathy with markedly increased liver enzymes, inflammatory cytokines, and chemokines, which significantly induce local and systemic inflammation. Curcumin exhibits anti-inflammatory and antiviral characteristics in inflammatory and infectious diseases. Here we determined effects of curcumin on viral replications, cytokine and chemokine expressions, and liver damage in CVB3-infected Huh-7 cells. The mouse-adapted CVB3 strain was used to investigate the antiviral and anti-inflammatory effects of curcumin on CVB3-induced hepatitis in a mouse model. In vitro studies showed that curcumin reduced viral protein and titer levels and increased cell viability. Curcumin enhanced the heme oxygenase-1 (HO-1) protein level and decreased the levels of cleaved caspase-3 protein and mRNA of gene encoding C-X-C motif chemokine 10 in infected cells. In vivo studies showed that curcumin improved the survival rate and clinical scores in mice and reduced the viral titer in the liver during CVB3 infection. Moreover, the HO-1 levels were increased, and the cleaved caspase-3 levels were diminished in the CVB3-infected liver. Curcumin reduced the levels of interferon (IFN)-γ and monokine induced by IFN-γ in liver and levels of interleukin (IL)-8 in serum, but increased levels of regulated activation, normal T cell expression in liver and levels of IL-10 in serum of CVB3-infected mice. In summary, curcumin presents antiviral and anti-inflammation efficacies in CVB3 infection in vitro and in vivo; these results provide potential evidence on the feasibility of curcumin for clinical treatment.

Roles of Nrf2/HO-1 and ICAM-1 in the Protective Effect of Nano-Curcumin against Copper-Induced Lung Injury

Copper (Cu) is an essential trace element for maintaining normal homeostasis in living organisms. Yet, an elevated level of Cu beyond homeostatic capacity may lead to oxidative damage of cellular components in several organs, including the lungs. This work investigated the effects of curcumin (Curc) and nano-curcumin (nCurc) against Cu-induced lung injury, accenting the roles of oxidative stress, inflammation, and the nuclear factor erythroid 2-related factor/heme oxygenase-1 Nrf2/HO-1 pathway. Rats were challenged with 100 mg/kg of copper sulfate (CuSO4) while being treated with Curc or nCurc for 7 days. Cu-triggered lung oxidative stress detected as dysregulation of oxidative/antioxidant markers, a downregulation of Nrf-2/HO-1 signaling, and an increase in the inflammatory markers interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and intracellular adhesion molecule-1 (ICAM-1). Additionally, it decreased the expression of lung-specific proteins, surfactant protein-C (SP-C), and mucin-1 (MUC-1), induced apoptosis, and caused changes in lung histology. Curc and nCurc alleviated CuSO4-induced lung injury by suppressing oxidative damage and inflammation and activating Nrf-2/HO-1. They also prevented apoptosis and restored the normal expression of SP-C and MUC-1. We concluded that nCurc exhibited superior efficacy compared with Curc in mitigating CuSO4-induced lung injury. This was associated with reduced oxidative stress, inflammation, and apoptotic responses and increased Nrf2/HO-1 signaling and expression of SP-C and MUC-1.

A systematic review of the research progress of traditional Chinese medicine against pulmonary fibrosis: from a pharmacological perspective

Pulmonary fibrosis is a chronic progressive interstitial lung disease caused by a variety of etiologies. The disease can eventually lead to irreversible damage to the lung tissue structure, severely affecting respiratory function and posing a serious threat to human health. Currently, glucocorticoids and immunosuppressants are the main drugs used in the clinical treatment of pulmonary fibrosis, but their efficacy is limited and they can cause serious adverse effects. Traditional Chinese medicines have important research value and potential for clinical application in anti-pulmonary fibrosis. In recent years, more and more scientific researches have been conducted on the use of traditional Chinese medicine to improve or reduce pulmonary fibrosis, and some important breakthroughs have been made. This review paper systematically summarized the research progress of pharmacological mechanism of traditional Chinese medicines and their active compounds in improving or reducing pulmonary fibrosis. We conducted a systematic search in several main scientific databases, including PubMed, Web of Science, and Google Scholar, using keywords such as idiopathic pulmonary fibrosis, pulmonary fibrosis, interstitial pneumonia, natural products, herbal medicine, and therapeutic methods. Ultimately, 252 articles were included and systematically evaluated in this analysis. The anti-fibrotic mechanisms of these traditional Chinese medicine studies can be roughly categorized into 5 main aspects, including inhibition of epithelial-mesenchymal transition, anti-inflammatory and antioxidant effects, improvement of extracellular matrix deposition, mediation of apoptosis and autophagy, and inhibition of endoplasmic reticulum stress. The purpose of this article is to provide pharmaceutical researchers with information on the progress of scientific research on improving or reducing Pulmonary fibrosis with traditional Chinese medicine, and to provide reference for further pharmacological research.

Accelerating synergistic effects of preconditioned mesenchymal stem cells with Crocin and dexamethasone in pulmonary epithelial cells injury

Chemical warfare victims suffer from bronchiolitis and chronic pulmonary obstruction caused by sulfur mustard (SM) toxicity. Despite the mesenchymal stem cells capacity to alleviate inflammation, their low survival rate under oxidative stress severely limits their effectiveness. This study aimed to examine how natural (Crocin) and synthetic (Dexamethasone) antioxidants might affect MSC efficacy. MSCs were treated with the optimal doses of Crocin (Cr.), Dexamethasone (Dex.), and their combination. The A549 cells line was pretreated with the optimal dose of the CEES to mimic the lung disease. Then, the affected A549 cells were exposed to the preconditioned MSCs and conditioned media, and then their survival rates were estimated by MTTor2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Annexin-V PI apoptosis test was conducted for MSCs and A549 cells. Reactive Oxygen Species (ROS) assay and Enzyme-linked immunosorbent assay (ELISA) test demonstrated the percentage of production of ROS and the cytokines levels in A549/CEES, respectively. The results revealed significant increases in Cr. + Dex. treated MSCs (P < .01) and A549 cells treated with MSCs-CM/Cr/Dex (P < .01) groups' survival. The apoptosis rate and ROS production were reduced in the MSCs-CM/Cr/Dex. Also, considerable decreases in IL-1β (P < .01) and IL-6 (P < .01) and a significant increase in IL-10 (P < .05) in treated A549/CEES by Cr/Dex and MSCs-CM/Cr/Dex supported the synergistic effects of Crocin and Dexamethasone.

Combined inhibition of histone deacetylase and cytidine deaminase improves epigenetic potency of decitabine in colorectal adenocarcinomas

BACKGROUND

Targeting the epigenome of cancerous diseases represents an innovative approach, and the DNA methylation inhibitor decitabine is recommended for the treatment of hematological malignancies. Although epigenetic alterations are also common to solid tumors, the therapeutic efficacy of decitabine in colorectal adenocarcinomas (COAD) is unfavorable. Current research focuses on an identification of combination therapies either with chemotherapeutics or checkpoint inhibitors in modulating the tumor microenvironment. Here we report a series of molecular investigations to evaluate potency of decitabine, the histone deacetylase inhibitor PBA and the cytidine deaminase (CDA) inhibitor tetrahydrouridine (THU) in patient derived functional and p53 null colon cancer cell lines (CCCL). We focused on the inhibition of cell proliferation, the recovery of tumor suppressors and programmed cell death, and established clinical relevance by evaluating drug responsive genes among 270 COAD patients. Furthermore, we evaluated treatment responses based on CpG island density.

RESULTS

Decitabine caused marked repression of the DNMT1 protein. Conversely, PBA treatment of CCCL recovered acetylation of histone 3 lysine residues, and this enabled an open chromatin state. Unlike single decitabine treatment, the combined decitabine/PBA treatment caused > 95% inhibition of cell proliferation, prevented cell cycle progression especially in the S and G2-phase and induced programmed cell death. Decitabine and PBA differed in their ability to facilitate re-expression of genes localized on different chromosomes, and the combined decitabine/PBA treatment was most effective in the re-expression of 40 tumor suppressors and 13 genes typically silenced in cancer-associated genomic regions of COAD patients. Furthermore, this treatment repressed expression of 11 survival (anti-apoptotic) genes and augmented expression of X-chromosome inactivated genes, especially the lncRNA Xist to facilitate p53-mediated apoptosis. Pharmacological inhibition of CDA by THU or its gene knockdown prevented decitabine inactivation. Strikingly, PBA treatment recovered the expression of the decitabine drug-uptake transporter SLC15A1, thus enabling high tumor drug-loads. Finally, for 26 drug responsive genes we demonstrated improved survival in COAD patients.

CONCLUSION

The combined decitabine/PBA/THU drug treatment improved drug potency considerably, and given their existing regulatory approval, our findings merit prospective clinical trials for the triple combination in COAD patients.

Curcumin preconditioned mesenchymal stem cells derived exosomes transplantation ameliorate and protect against non- alcoholic steatohepatitis by regulation the expression of key genes of inflammation and oxidative stress

BACKGROUND

Mesenchymal stem cells (MSCs) derived exosomes (MSCs/Exo) is considered a new strategy in cell free regenerative therapy. Curcumin preconditioning of MSCs reported to improve the anti- inflammatory and immunomodulatory properties of MSCs. We investigated the efficacy of exosome (Exo) obtained from curcumin-preconditioned MSCs (MSCs/Exo-Cur) vs. MSC/Exo without curcumin to ameliorate and prevent recurrence of non-alcoholic fatty liver (NASH) disease.

METHODS AND RESULTS

In-vivo, methionine/choline-deficient diet (MCD) induced mice non-alcoholic fatty liver disease (NASH) were injected with MSCs/Exo without curcumin or MSCs/Exo-Cur with curcumin. We found that mice treated with MSCs/Exo-Cur had significantly ameliorated steatosis, inflammation, as evaluated by the reduced fibrosis in histopathological examination, decreased the serum level of liver enzymes (p < 0.001), liver triglycerides (TG) (p < 0.001) and cholesterol (Ch) (p < 0.001) and increased the lipid peroxidation (p < 0.001) compared to MSCs/Exo-treated mice. These effects remained for 3 months after treatment in MSCs/Exo-Cur-treated mice while features of NASH returned in MSCs/Exo-treated group. In vitro, HepG2 cells were cultured with palmitic acid (PA) and treated with MSCs/Exo or MSCs/Exo-Cur: the MSCs/Exo-Cur exposure reversed the lipotoxic effect from 4.5 to 1.7 fold vs 4.0 fold in MSCs/Exo and oxidative stress in PA-treated HepG2 cells (p < 0.001). We found that MSCs/Exo-Cur regulated the key markers of inflammatory and oxidative stress, genes responsible for fibrogenesis of the liver, key genes of lipid synthesis and transport . Interestingly, MSCs/Exo-Cur significantly down regulated the ASK-JNK-BAX genes involved in mitochondrial stress and apoptosis compared to MSCs/Exo (p < 0.001).

CONCLUSION

Our study indicated that exosomes derived from curcumin preconditioned MSCs were able to ameliorate and protect against recurrence of NASH and regulated inflammatory, oxidative stress and mitochondrial-dependent apoptosis ASK-JNK-BAX genes.

Sensitization of GSH synthesis by curcumin curtails acrolein-induced alveolar epithelial apoptosis via Keap1 cysteine conjugation: A randomized controlled trial and experimental animal model of pneumonitis

INTRODUCTION

Epidemiological studies have reported an association between exposures to ambient air pollution and respiratory diseases, including chronic obstructive pulmonary disease (COPD). Pneumonitis is a critical driving factor of COPD and exposure to air pollutants (e.g., acrolein) is associated with increased incidence of pneumonitis.

OBJECTIVES

Currently available anti-inflammatory therapies provide little benefit against respiratory diseases. To this end, we investigated the preventive role of curcumin against air pollutant-associated pneumonitis and its underlying mechanism.

METHODS

A total of 40 subjects was recruited from Chengdu, China which is among the top three cities in terms of respiratory mortality related to air pollution. The participants were randomly provided either placebo or curcumin supplements for 2 weeks and blood samples were collected at the baseline and at the end of the intervention to monitor systemic markers. In our follow up mechanistic study, C57BL/6 mice (n = 40) were randomly allocated into 4 groups: Control group (saline + no acrolein), Curcumin only group (curcumin + no acrolein), Acrolein only group (saline + acrolein), and Acrolein + Curcumin group (curcumin + acrolein). Curcumin was orally administered at 100 mg/kg body weight once a day for 10 days, and then the mice were subjected to nasal instillation of acrolein (5 mg/kg body weight). Twelve hours after single acrolein exposure, all mice were euthanized.

RESULTS

Curcumin supplementation, with no noticeable adverse responses, reduced circulating pro-inflammatory cytokines in association with clinical pneumonitis as positive predictive while improving those of anti-inflammatory cytokines. In the pre-clinical study, curcumin reduced pneumonitis manifestations by suppression of intrinsic and extrinsic apoptotic signaling, which is attributed to enhanced redox sensing of Nrf2 and thus sensitized synthesis and restoration of GSH, at least in part, through curcumin-Keap1 conjugation.

CONCLUSIONS

Our study collectively suggests that curcumin could provide an effective preventive measure against air pollutant-enhanced pneumonitis and thus COPD.

Monomeric compounds from traditional Chinese medicine: New hopes for drug discovery in pulmonary fibrosis

Pulmonary fibrosis (PF) is a chronic and irreversible pulmonary disease, and can lead to decreased lung function, respiratory failure and even death. The pathogenesis research and treatment strategy of PF significantly lag behind the medical progress and clinical needs. The treatment of this disease remains a thorny clinical problem, and the effective therapeutic drugs are still limited. Monomeric compounds from traditional Chinese medicine own various biological activities and high safety. They play a broad part in treating diseases and is also a candidate drug for preventing and treating PF. In this paper, we reviewed the mechanism of action and potential value of various anti-PF monomeric compounds from traditional Chinese medicine. These monomeric compounds can attenuate inflammatory response, oxidative stress, epithelial mesenchymal transformation and other processes of lung through many signaling pathways, and inhibit the activation and differentiation of fibroblasts, thus contributing to the treatment of PF. This review can provide new ideas for the development of anti-PF drugs in high efficiency with low toxicity.

Polyphenols from Chinese Herbal Medicine: Molecular Mechanisms and Therapeutic Targets in Pulmonary Fibrosis

Pulmonary fibrosis (PF) is a highly confounding and fatal pathological process with finite treatment options. Multiple factors such as oxidative and immune/inflammation involve key pathological processes in chronic lung disease, and their intimate interactions mediate chronic lung damage, denudation of the alveolar epithelium, hyperproliferation of type II alveolar epithelial cells (AECIIs), proliferation and differentiation of fibroblasts, and the permeability of microvessels. We reviewed the classic mechanism of PF and highlighted a few emerging mechanisms for studying complex networks in lung disease pathology. Polyphenols, as a multi-target drug, has excellent potential in the treatment of pulmonary fibrosis. We then reviewed recent advances in discovering phenolic compounds from fruits, tea, and medical herbs with the bioactivities of simultaneously regulating multiple factors (e.g., oxidative stress, inflammation, autophagy, apoptosis, pyroptosis) for minimizing pulmonary fibrosis injury. These compounds include resveratrol, curcumin, salvianolic acid B, epigallocatechin-3-gallate, gallic acid, corilagin. Each phenolic compound can exert its anti-PF effect through various mechanisms, and the signaling pathways involved in different phenolic compounds are not the same. This review summarized the available evidence on phenolic compounds' effectiveness in pulmonary diseases and explored the molecular mechanisms and therapeutic targets of phenolic compounds from Chinese herbal medicine with the properties of inhibition of ongoing fibrogenesis and resolution of existing fibrosis.

Potential pre-activation strategies for improving therapeutic efficacy of mesenchymal stem cells: current status and future prospects

Mesenchymal stem cell (MSC)-based therapy has been considered as a promising approach targeting a variety of intractable diseases due to remarkable multiple effect of MSCs, such as multilineage differentiation, immunomodulatory property, and pro-regenerative capacity. However, poor engraftment, low survival rate of transplanted MSC, and impaired donor-MSC potency under host age/disease result in unsatisfactory therapeutic outcomes. Enhancement strategies, including genetic manipulation, pre-activation, and modification of culture method, have been investigated to generate highly functional MSC, and approaches for MSC pre-activation are highlighted. In this review, we summarized the current approaches of MSC pre-activation and further classified, analysed the scientific principles and main characteristics of these manipulations, and described the pros and cons of individual pre-activation strategies. We also discuss the specialized tactics to solve the challenges in this promising field so that it improves MSC therapeutic functions to serve patients better.

Targeting Oxidative Stress as a Therapeutic Approach for Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial lung disease characterized by an abnormal reepithelialisation, an excessive tissue remodelling and a progressive fibrosis within the alveolar wall that are not due to infection or cancer. Oxidative stress has been proposed as a key molecular process in pulmonary fibrosis development and different components of the redox system are altered in the cellular actors participating in lung fibrosis. To this respect, several activators of the antioxidant machinery and inhibitors of the oxidant species and pathways have been assayed in preclinical in vitro and in vivo models and in different clinical trials. This review discusses the role of oxidative stress in the development and progression of IPF and its underlying mechanisms as well as the evidence of oxidative stress in human IPF. Finally, we analyze the mechanism of action, the efficacy and the current status of different drugs developed to inhibit the oxidative stress as anti-fibrotic therapy in IPF.

Nrf2-Related Therapeutic Effects of Curcumin in Different Disorders

Curcumin is a natural polyphenol with antioxidant, antibacterial, anti-cancer, and anti-inflammation effects. This substance has been shown to affect the activity of Nrf2 signaling, a pathway that is activated in response to stress and decreases levels of reactive oxygen species and electrophilic substances. Nrf2-related effects of curcumin have been investigated in different contexts, including gastrointestinal disorders, ischemia-reperfusion injury, diabetes mellitus, nervous system diseases, renal diseases, pulmonary diseases, cardiovascular diseases as well as cancers. In the current review, we discuss the Nrf2-mediated therapeutic effects of curcumin in these conditions. The data reviewed in the current manuscript indicates curcumin as a potential activator of Nrf2 and a therapeutic substance for the protection of cells in several pathological conditions.

Nrf2 Regulation by Curcumin: Molecular Aspects for Therapeutic Prospects

Nuclear factor erythroid 2 p45-related factor (2Nrf2) is an essential leucine zipper protein (bZIP) that is primarily located in the cytoplasm under physiological conditions. Nrf2 principally modulates endogenous defense in response to oxidative stress in the brain.In this regard, Nrf2 translocates into the nucleus and heterodimerizes with the tiny Maf or Jun proteins. It then attaches to certain DNA locations in the nucleus, such as electrophile response elements (EpRE) or antioxidant response elements (ARE), to start the transcription of cytoprotective genes. Many neoplasms have been shown to have over activated Nrf2, strongly suggesting that it is responsible for tumors with a poor prognosis. Exactly like curcumin, Zinc-curcumin Zn (II)-curc compound has been shown to induce Nrf2 activation. In the cancer cell lines analyzed, Zinc-curcumin Zn (II)-curc compound can also display anticancer effects via diverse molecular mechanisms, including markedly increasing heme oxygenase-1 (HO-1) p62/SQSTM1 and the Nrf2 protein levels along with its targets. It also strikingly decreases the levels of Nrf2 inhibitor, Kelch-like ECH-associated protein 1 (Keap1) protein.As a result, the crosstalk between p62/SQSTM1 and Nrf2 could be used to improve cancer patient response to treatments. The interconnected anti-inflammatory and antioxidative properties of curcumin resulted from its modulatory effects on Nrf2 signaling pathway have been shown to improve insulin resistance. Curcumin exerts its anti-inflammatory impact through suppressing metabolic reactions and proteins such as Keap1 that provoke inflammation and oxidation. A rational amount of curcumin-activated antioxidant Nrf2 HO-1 and Nrf2-Keap1 pathways and upregulated the modifier subunit of glutamate-cysteine ligase involved in the production of the intracellular antioxidant glutathione. Enhanced expression of glutamate-cysteine ligase, a modifier subunit (GLCM), inhibited transcription of glutamate-cysteine ligase, a catalytic subunit (GCLC). A variety of in vivo, in vitro and clinical studies has been done so far to confirm the protective role of curcumin via Nrf2 regulation. This manuscript is designed to provide a comprehensive review on the molecular aspects of curcumin and its derivatives/analogs via regulation of Nrf2 regulation.

Iron overload and mitochondrial dysfunction orchestrate pulmonary fibrosis

Pulmonary fibrosis (PF) is a chronic, progressive heterogeneous disease of lung tissues with poor lung function caused by scar tissue. Due to our limited understanding of its mechanism, there is currently no treatment strategy that can prevent the development of PF. In recent years, iron accumulation and mitochondrial damage have been reported to participate in PF, and drugs that reduce iron content and improve mitochondrial function have shown significant efficacy in animal experimental models. Excessive iron leads to mitochondrial impairment, which may be the key cause that results in the dysfunction of various kinds of pulmonary cells and further promotes PF. As an emerging research hotspot, there are few targeted effective therapeutic strategies at present due to limited mechanistic understanding. In this review, the roles of iron homeostasis imbalance and mitochondrial damage in PF are summarized and discussed, highlighting a promising direction for finding truly effective therapeutics for PF.

Curcumin Improves Epithelial Barrier Integrity of Caco-2 Monolayers by Inhibiting Endoplasmic Reticulum Stress and Subsequent Apoptosis

Curcumin is a natural polyphenol and is supposed to possess antioxidant, anti-inflammatory, anticancer, and antiapoptotic properties. Although some studies have reported the therapeutic effects of curcumin on ulcerative colitis (UC), the specific mechanism remains unclear. An in vitro coculture model of Caco-2 and differentiated THP-1 cells was established. After administration of curcumin (10 μM), Western blot analysis was performed to evaluate the protein levels of tight junction (TJ) proteins zonula occludens- (ZO-) 1 and claudin-1. Annexin V-APC/7-AAD assays and flow cytometry were conducted to assess Caco-2 cell apoptosis. The expression levels of oxidative stress and endoplasmic reticulum stress- (ERS-) related molecules were determined by Western blot analysis. Curcumin administration significantly upregulated ZO-1 and claudin-1 protein levels and reduced Caco-2 cell apoptosis. The protein levels of oxidative stress markers inducible nitric oxide synthase (iNOS) and γH2AX and ERS-induced apoptosis-related molecules C/EBP homologous protein (CHOP) and cleaved caspase-12 were significantly downregulated upon curcumin treatment. Furthermore, curcumin administration greatly blocked the protein kinase-like endoplasmic reticulum kinase- (PERK-) eukaryotic translation initiation factor 2α- (eIF2α-) activating transcription factor 4- (ATF4-) CHOP signaling pathway. Curcumin enhanced intestinal epithelial barrier integrity in the in vitro coculture model by upregulating TJ protein expressions and reducing intestinal epithelial cell apoptosis. The potential mechanisms may be suppression of ERS and subsequent apoptosis.

Effect of Curcumin on Alterations of Alveolar Bone Remodeling and Expression of Receptor Activator of Nuclear Factor-κ B Ligand in Rat Tooth During Tooth Movement

Objective: To evaluate the effect of Curcumin on Alterations of Alveolar Bone Remodeling and Expression of RANKL in Rat Tooth during Tooth Movement. Methods: 64 SD rats were randomly divided into 4 groups, Model, Adrb2, Cur and Cur + Pro groups. The rat orthodontic teeth movement models were established.The rats were injected corresponding reagents according to weight and were sacrificed on day 0, 7, 14 and 21. The movement distance of first molar of rats was measured by Vernier caliper.The numbers of osteoclasts were observed through TRAP staining. The change of micro-structure of alveolar bone was evaluated by Micro-CT. Results: The trends of the distance of teeth movement and numbers of osteoclast were the same: Cur group β Adrb2 group > Model groups Cur+Pro group (P < 0.05). Micro-CT scan showed that curcumin could reduce the bone volume fraction (BV/TV), bone trabecular density (MTPD), and increase the trabecular resolution (TB. SP). When propranolol was given at the same time, the effect of curcumin disappeared. Conclusion: Curcumin could promote the resorption of alveolar bone at the pressure side and increase the osteoclast numbers so that the alveolar bone became looser which was beneficial to the movement of orthodontic tooth.

Curcumin preconditioning enhances the efficacy of adipose-derived mesenchymal stem cells to accelerate healing of burn wounds

Background

Following recent findings from our group that curcumin preconditioning augments the therapeutic efficacy of adipose-derived stem cells in the healing of diabetic wounds in rats, we aimed to investigate the regenerative effects of curcumin preconditioned adipose-derived mesenchymal stem cells (ASCs) for better recovery of acid inflicted burns in this study.

Methods

ASCs were preconditioned with 5 μM curcumin for 24 hours and assessed for proliferation, migration, paracrine release potential and gene expression comparative to naïve ASCs. Subsequently, the healing capacity of curcumin preconditioned ASCs (Cur-ASCs) versus naïve ASCs was examined using acidic wounds in rats. For this, acid inflicted burns of 20 mm in diameter were made on the back of male Wistar rats. Then, 2 × 10⁶ cells of Cur-ASCs and naïve ASCs were intradermally injected in the wound periphery (n = 6) for comparison with an untreated saline control. Post-transplantation, wounds were macroscopically analysed and photographed to evaluate the percentage of wound closure and period of re-epithelization. Healed wound biopsies were excised and used for histological evaluation and expression analysis of wound healing markers at molecular level by quantitative PCR and western blotting.

Results

We found that Cur-ASCs exhibited greater proliferation, migration and paracrine potential in vitro. Further, Cur-ASCs showed more effective recovery than naïve ASCs as exhibited by gross morphology, faster wound closure and earlier re-epithelialization. Masson’s trichrome and hematoxylin and eosin staining demonstrated the improved architecture of the healing burns, as evidenced by reduced infiltration of inflammatory cells, compact collagen and marked granulation in Cur-ASC treated rats. Corroborating these findings, molecular assessment showed significantly reduced expressions of pro-inflammatory factors (interleukin-1 beta, interleukin-6, tumor necrosis factor alpha) a with striking upsurge of an oxidative marker (superoxide dismutase 1), pro-angiogenic factors (vascular endothelial growth factor, hepatocyte growth factor, hypoxia-inducible factor-1 alpha) and collagen markers (transforming growth factor beta 1, fibroblast growth factor-2, collagen type 1 alpha 1), verifying that Cur-ASCs modulate the regulation of pro-inflammatory and healing markers at burn sites.

Conclusions

Treatment with Cur-ASCs resulted in faster re-epithelization of acid inflicted burns compared to the treatment with naïve ASCs. Based on observed findings, we suggest the transplantation of Cur-ASCs is a valuable therapy for the potent clinical management of acidic burns.

Progress in Natural Compounds/siRNA Co-delivery Employing Nanovehicles for Cancer Therapy

Chemotherapy using natural compounds, such as resveratrol, curcumin, paclitaxel, docetaxel, etoposide, doxorubicin, and camptothecin, is of importance in cancer therapy because of the outstanding therapeutic activity and multitargeting capability of these compounds. However, poor solubility and bioavailability of natural compounds have limited their efficacy in cancer therapy. To circumvent this hurdle, nanocarriers have been designed to improve the antitumor activity of the aforementioned compounds. Nevertheless, cancer treatment is still a challenge, demanding novel strategies. It is well-known that a combination of natural products and gene therapy is advantageous over monotherapy. Delivery of multiple therapeutic agents/small interfering RNA (siRNA) as a potent gene-editing tool in cancer therapy can maximize the synergistic effects against tumor cells. In the present review, co-delivery of natural compounds/siRNA using nanovehicles are highlighted to provide a backdrop for future research.

Curcumin, a traditional spice component, can hold the promise against COVID-19?

The severity of the recent pandemic and the absence of any specific medication impelled the identification of existing drugs with potential in the treatment of Coronavirus disease-2019 (COVID-19), caused by severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). Curcumin, known for its pharmacological abilities especially as an anti-inflammatory agent, can be hypothesized as a potential candidate in the therapeutic regimen. COVID-19 has an assorted range of pathophysiological consequences, including pulmonary damage, elevated inflammatory response, coagulopathy, and multi-organ damage. This review summarizes the several evidences for the pharmacological benefits of curcumin in COVID-19-associated clinical manifestations. Curcumin can be appraised to hinder cellular entry, replication of SARS-CoV-2, and to prevent and repair COVID-19-associated damage of pneumocytes, renal cells, cardiomyocytes, hematopoietic stem cells, etc. The modulation and protective effect of curcumin on cytokine storm-related disorders are also discussed. Collectively, this review provides grounds for its clinical evaluation in the therapeutic management of SARS-CoV-2 infection.