Curcumin suppresses cardiac fibroblasts activities by regulating the proliferation and cell cycle via the inhibition of the p38 MAPK/ERK signaling pathway

Unveiling the emerging role of curcumin to alleviate ochratoxin A-induced muscle toxicity in grass carp (Ctenopharyngodon idella): in vitro and in vivo studies

BACKGROUND

Ochratoxin A (OTA), a globally abundant and extremely hazardous pollutant, is a significant source of contamination in aquafeeds and is responsible for severe food pollution. The developmental toxicity of OTA and the potential relieving strategy of natural products remain unclear. This study screened the substance curcumin (Cur), which had the best effect in alleviating OTA inhibition of myoblast proliferation, from 96 natural products and investigated its effect and mechanism in reducing OTA myotoxicity in vivo and in vitro.

METHODS

A total of 720 healthy juvenile grass carp, with an initial average body weight of 11.06 ± 0.05 g, were randomly assigned into 4 groups: the control group (without OTA and Cur), 1.2 mg/kg OTA group, 400 mg/kg Cur group, and 1.2 mg/kg OTA + 400 mg/kg Cur group. Each treatment consisted of 3 replicates (180 fish) for 60 d.

RESULTS

Firstly, we cultured, purified, and identified myoblasts using the tissue block culture method. Through preliminary screening and re-screening of 96 substances, we examined cell proliferation-related indicators such as cell viability and ultimately found that Cur had the best effect. Secondly, Cur could alleviate OTA-inhibited myoblast differentiation and myofibrillar development-related proteins (MyoG and MYHC) in vivo and in vitro and improve the growth performance of grass carp. Then, Cur could also promote the expression of OTA-inhibited protein synthesis-related proteins (S6K1 and TOR), which was related to the activation of the AKT/TOR signaling pathway. Finally, Cur could downregulate the expression of OTA-enhanced protein degradation-related genes (murf1, foxo3a, and ub), which was related to the inhibition of the FoxO3a signaling pathway.

CONCLUSIONS

In summary, our data demonstrated the effectiveness of Cur in alleviating OTA myotoxicity in vivo and in vitro. This study confirms the rapidity, feasibility, and effectiveness of establishing a natural product screening method targeting myoblasts to alleviate fungal toxin toxicity.

Review of the Protective Mechanism of Curcumin on Cardiovascular Disease

Cardiovascular diseases (CVDs) are the most common cause of death worldwide and has been the focus of research in the medical community. Curcumin is a polyphenolic compound extracted from the root of turmeric. Curcumin has been shown to have a variety of pharmacological properties over the past decades. Curcumin can significantly protect cardiomyocyte injury after ischemia and hypoxia, inhibit myocardial hypertrophy and fibrosis, improve ventricular remodeling, reduce drug-induced myocardial injury, improve diabetic cardiomyopathy(DCM), alleviate vascular endothelial dysfunction, inhibit foam cell formation, and reduce vascular smooth muscle cells(VSMCs) proliferation. Clinical studies have shown that curcumin has a protective effect on blood vessels. Toxicological studies have shown that curcumin is safe. But high doses of curcumin also have some side effects, such as liver damage and defects in embryonic heart development. This article reviews the mechanism of curcumin intervention on CVDs in recent years, in order to provide reference for the development of new drugs in the future.

A Mechanistic Review on Therapeutic Potential of Medicinal Plants and their Pharmacologically Active Molecules for Targeting Metabolic Syndrome

Metabolic syndrome (MetS) therapy with phytochemicals is an emerging field of study with therapeutic potential. Obesity, insulin resistance, high blood pressure, and abnormal lipid profiles are all components of metabolic syndrome, which is a major public health concern across the world. New research highlights the promise of phytochemicals found in foods, including fruits, vegetables, herbs, and spices, as a sustainable and innovative method of treating this illness. Anti-inflammatory, antioxidant, and insulin-sensitizing qualities are just a few of the many positive impacts shown by bioactive substances. Collectively, they alleviate the hallmark symptoms of metabolic syndrome by modulating critical metabolic pathways, boosting insulin sensitivity, decreasing oxidative stress, and calming chronic low-grade inflammation. In addition, phytochemicals provide a multimodal strategy by targeting not only adipose tissue but also the liver, skeletal muscle, and vascular endothelium, all of which have a role in the pathogenesis of MetS. Increasing evidence suggests that these natural chemicals may be useful in controlling metabolic syndrome as a complementary treatment to standard medication or lifestyle changes. This review article emphasizes the therapeutic potential of phytochemicals, illuminating their varied modes of action and their ability to alleviate the interconnected causes of metabolic syndrome. Phytochemical-based interventions show promise as a novel and sustainable approach to combating the rising global burden of metabolic syndrome, with the ultimate goal of bettering public health and quality of life.

Curcumin upregulates transforming growth factor-β1, its receptors, and vascular endothelial growth factor expressions in an in vitro human gingival fibroblast wound healing model

BACKGROUND

Curcumin accelerates healing of oral wounds; however, the responsible mechanisms remain underexplored. Our hypothesis is curcumin regulates the expression of wound healing-related genes in human gingival fibroblasts (hGFs). This study investigated whether curcumin regulates transforming growth factor (TGF)-β1, type I TGF-β receptor (TGF-βRI), type II TGF-β receptor (TGF-βRII), and vascular endothelial growth factor (VEGF) expression in unwounded hGFs and an in vitro hGF wound healing model.

METHODS

The cytotoxicity of curcumin was evaluated using the MTT assay. Unwounded hGFs were treated with non-cytotoxic concentrations of curcumin for 24 h. Gene expression was determined by quantitative polymerase chain reaction. Then, hGFs were treated with 1 µM curcumin in an in vitro wound healing model. PD98059 pretreatment was performed to determine whether extracellular signal-regulated kinase (ERK) signaling was required for regulation of gene expression by curcumin.

RESULTS

Curcumin at 0.1-20 µM caused no significant change in cell viability. In unwounded hGFs, curcumin had no significant effect on TGF-β1, TGF-βRI, TGF-βRII, or VEGF expression. Conversely, curcumin significantly upregulated the expression of these genes in the in vitro wound healing model. PD98059 significantly attenuated the curcumin-stimulated TGF-βRI, TGF-βRII, and VEGF expression, whereas it had no effect on TGF-β1 expression.

CONCLUSIONS

Curcumin upregulated TGF-β1, TGF-βRI, TGF-βRII, and VEGF expression in an in vitro hGF wound healing model. The ERK pathway is required for TGF-βRI, TGF-βRII, and VEGF induction by curcumin. Our findings support the development of curcumin as a therapeutic agent for gingival ulcers.

Current clinical developments in curcumin-based therapeutics for cancer and chronic diseases

The last decade has seen an unprecedented rise in the prevalence of chronic diseases worldwide. Different mono-targeted approaches have been devised to treat these multigenic diseases, still most of them suffer from limited success due to the off-target debilitating side effects and their inability to target multiple pathways. Hence a safe, efficacious, and multi-targeted approach is the need for the hour to circumvent these challenging chronic diseases. Curcumin, a natural compound extracted from the rhizomes of Curcuma longa, has been under intense scrutiny for its wide medicinal and biological properties. Curcumin is known to manifest antibacterial, antiinflammatory, antioxidant, antifungal, antineoplastic, antifungal, and proapoptotic effects. A plethora of literature has already established the immense promise of curcuminoids in the treatment and clinical management of various chronic diseases like cancer, cardiovascular, metabolic, neurological, inflammatory, and infectious diseases. To date, more than 230 clinical trials have opened investigations to understand the pharmacological aspects of curcumin in human systems. Still, further randomized clinical studies in different ethnic populations warrant its transition to a marketed drug. This review summarizes the results from different clinical trials of curcumin-based therapeutics in the prevention and treatment of various chronic diseases.

Topological and system-level protein interaction network (PIN) analyses to deduce molecular mechanism of curcumin

Curcumin is an important bioactive component of turmeric and also one of the important natural products, which has been investigated extensively. The precise mode of action of curcumin and its impact on system level protein networks are still not well studied. To identify the curcumin governed regulatory action on protein interaction network (PIN), an interectome was created based on 788 key proteins, extracted from PubMed literatures, and constructed by using STRING and Cytoscape programs. The PIN rewired by curcumin was a scale-free, extremely linked biological system. MCODE plug-in was used for sub-modulization analysis, wherein we identified 25 modules; ClueGo plug-in was used for the pathway’s enrichment analysis, wherein 37 enriched signalling pathways were obtained. Most of them were associated with human diseases groups, particularly carcinogenesis, inflammation, and infectious diseases. Finally, the analysis of topological characteristic like bottleneck, degree, GO term/pathways analysis, bio-kinetics simulation, molecular docking, and dynamics studies were performed for the selection of key regulatory proteins of curcumin-rewired PIN. The current findings deduce a precise molecular mechanism that curcumin might exert in the system. This comprehensive in-silico study will help to understand how curcumin induces its anti-cancerous, anti-inflammatory, and anti-microbial effects in the human body.

Qingjie Fuzheng granules inhibit colorectal cancer cell growth by the PI3K/AKT and ERK pathways

BACKGROUND

Qingjie Fuzheng granules (QFGs) are part of a traditional Chinese medicine formula, which has been widely used and found to be clinically effective with few side effects in various cancer treatments, including colorectal cancer (CRC). However, the precise mechanisms and molecular signaling pathways involved in the activity of QFGs’ anticancer effect have not been reported in the literature. In this study, we hypothesized that QFGs can inhibit the growth of colorectal cancer cells, and that its mechanism is closely related to one or more intracellular signal transduction pathways.

AIM

To better evaluate the mechanism underlying the anti-cancer effect of QFGs on the CRC cell lines HCT-116 and HCT-8.

METHOD

First, we measured cell viability and cytotoxicity by performing MTT and lactate dehydrogenase (LDH) assays. We evaluated the role of QFGs in cell proliferation and apoptosis by assessing colony formation and analyzing Hoechst 33258 staining. Second, cell cycle and apoptosis rates were measured by fluorescence activated cell sorting, and the expression levels of survivin, cyclin D1, CDK4, p21, Bax, Bcl-2, Fas, FasL, and cleaved-caspase-3/-8/-9 were measured by performing western blots and caspase activity assays. Furthermore, inhibitors of caspase-3/-8/-9 were used to elucidate the specific apoptosis pathway induced by QFGs in cancer cells. Finally, activation of the PI3K/AKT and ERK signaling pathways was examined using the western blot assay to investigate the possible mechanism.

RESULTS

MTT and LDH assays revealed that after 0.5-2.0 mg/mL of QFGs treatment, cell viability was reduced by (6.90% ± 1.03%)–(59.70% ± 1.51%) (HCT-116; P < 0.05) and (5.56% ± 4.52%)–(49.44% ± 2.47%) (HCT-8; P < 0.05), and cytotoxicity was increased from 0.52 ± 0.023 to 0.77 ± 0.002 (HCT-116; P < 0.01) and from 0.56 ± 0.054 to 0.81 ± 0.044 (HCT-8; P < 0.01) compared with the non-QFGs treatment groups. Additionally, colony formation and Hoechst 33258 staining assays showed that QFGs inhibited proliferation and induced apoptosis in CRC cells. QFGs also increased the expression levels of Bax, Fas and FasL, decreased the level of Bcl-2, and stimulated the activation of caspase-3/-8/-9, which were revealed by western blot and caspase activity assays. In contrast, when adding the three caspase inhibitors, the suppression effect of QFGs on cell viability and apoptosis were markedly inhibited. Moreover, QFGs suppressed the phosphorylation levels of PI3K, AKT and ERK.

CONCLUSION

These results demonstrated that QFGs can inhibit CRC cell proliferation and induce apoptosis by suppressing the PI3K/AKT and ERK signaling pathways.

Curcumin protects islet cells from glucolipotoxicity by inhibiting oxidative stress and NADPH oxidase activity both in vitro and in vivo

Curcumin possesses medicinal properties that are beneficial in various diseases, such as heart disease, cancer, and type 2 diabetes mellitus (T2 DM). It has been proposed that pancreatic beta cell dysfunction in T2 DM is promoted by oxidative stress caused by NADPH oxidase over-activity. The aim of the present study was to evaluate the efficacy of curcumin as a protective agent against high glucose/palmitate (HP)-induced islet cell damage and in streptozotocin (STZ)-induced DM rats. INS-1 cells were exposed to HP with or without curcumin. Cell proliferation, islet cell morphological changes, reactive oxygen species production, superoxide dismutase and catalase activity, insulin levels, NADPH oxidase subunit expression, and the expression of apoptotic factors by INS-1 cells were observed. Our results show that curcumin can effectively inhibit the impairment of cell proliferation and activated oxidative stress, increase insulin levels, and reduce the high expression of NADPH oxidase subunits and apoptotic factors induced by HP in INS-1 cells. The STZ-induced DM rat model was also used to determine whether curcumin can protect islets in vivo. Our results show that curcumin significantly reduced pathological damage and increased insulin levels of islets in STZ-induced DM rats. Curcumin also successfully inhibited the high expression of NADPH oxidase subunits and apoptotic factors in STZ-induced DM rats. These results suggest that curcumin is able to attenuate HP-induced oxidative stress in islet cells and protect these cells from apoptosis by modulating the NADPH pathway. In view of its efficiency, curcumin has potential for translation applications in protecting islets from glucolipotoxicity.