Curcumin protects cardiac myocyte against hypoxia-induced apoptosis through upregulating miR-7a/b expression

Research progress on the natural products in the intervention of myocardial infarction

Coronary heart disease is a prevalent cardiovascular ailment globally, with myocardial infarction (MI) being one of its most severe manifestations. The morbidity and mortality of MI are escalating, showing an increasing trend among younger, highly educated individuals, thereby posing a serious threat to public health. Currently, thrombolysis, percutaneous coronary intervention, and coronary artery bypass grafting are the primary clinical treatments for MI. Although these methods significantly reduce patient mortality, complications often result in poor prognoses. Due to limitations in chemical synthetic drug research, the focus has shifted towards developing herbs based on natural substances. Natural medicines represent a novel approach for safer and more effective MI management and treatment. They can control multiple pathogenic variables by targeting various pathways and systems. This paper investigates the molecular mechanisms of MI and evaluates the application of natural products and medicinal plants in MI treatment over the past 5 years, demonstrating their specific good therapeutic potential and superior tolerance. These natural therapies have been shown to mitigate myocardial cell damage caused by MI through mechanisms such as oxidative stress, inflammation, apoptosis, angiogenesis, myocardial fibrosis, autophagy, endoplasmic reticulum stress, mitophagy, and pyroptosis. This review offers the latest insights into the application of natural products and medicinal plants in MI treatment, elucidating their mechanisms of action and serving as an important reference for MI prevention.

Unveiling the hidden effects of hypoxia: Pituitary damage and hormonal imbalance in fat greenling (Hexagrammos otakii)

BACKGROUND

In fisheries, hypoxia stress is one of the most common environmental stresses that often lead to the death of large numbers of fish and cause significant economic losses. The pituitary, an important endocrine gland, lies below the hypothalamus region of the brain. It plays a crucial part in controlling vital physiological functions in fish, such as growth, reproduction, and responses to stress. However, the detailed mechanisms of how hypoxia affects these physiological processes via the pituitary remain largely unknown.

METHODS

Fat greenlings (Hexagrammous otakii) were exposed to different dissolved oxygen (DO = 7. 6 mg/L and DO = 2 mg/L) for 24 h. miRNA-mRNA association analysis of H. otakii pituitary after hypoxia stress. Detecting apoptosis in H. otakii pituitary using Tunel and qPCR. Subsequent detection of hormones in H. otakii liver, gonads and serum by ELISA.

RESULTS

In this study, hypoxia causes immune system disorders and inflammatory responses through the combined analysis of miRNAs and mRNAs. Subsequent verification indicated a significant accumulation of reactive oxygen species (ROS) subsequent to hypoxia treatment. The overproduction of ROS cause oxidative stress and apoptosis in the pituitary, ultimately causing pituitary damage and reduced growth hormone and luteinising hormone release.

CONCLUSIONS

According to the association study of miRNA-mRNA, apoptosis problems caused by hypoxia stress result in H. otakii pituitary damage. In the meantime, this work clarifies the possible impact of hypoxia-stress on the pituitary cells, as well as on the gonadal development and growth of H. otakii.

Mitochondrial Dysfunction: A Roadmap for Understanding and Tackling Cardiovascular Aging

Cardiovascular aging is a progressive remodeling process constituting a variety of cellular and molecular alterations that are closely linked to mitochondrial dysfunction. Therefore, gaining a deeper understanding of the changes in mitochondrial function during cardiovascular aging is crucial for preventing cardiovascular diseases. Cardiac aging is accompanied by fibrosis, cardiomyocyte hypertrophy, metabolic changes, and infiltration of immune cells, collectively contributing to the overall remodeling of the heart. Similarly, during vascular aging, there is a profound remodeling of blood vessel structure. These remodeling present damage to endothelial cells, increased vascular stiffness, impaired formation of new blood vessels (angiogenesis), the development of arteriosclerosis, and chronic vascular inflammation. This review underscores the role of mitochondrial dysfunction in cardiac aging, exploring its impact on fibrosis and myocardial alterations, metabolic remodeling, immune response remodeling, as well as in vascular aging in the heart. Additionally, we emphasize the significance of mitochondria-targeted therapies in preventing cardiovascular diseases in the elderly.

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.

Micro-Executor of Natural Products in Metabolic Diseases

Obesity, diabetes, and cardiovascular diseases are the major chronic metabolic diseases that threaten human health. In order to combat these epidemics, there remains a desperate need for effective, safe, and easily available therapeutic strategies. Recently, the development of natural product research has provided new methods and options for these diseases. Numerous studies have demonstrated that microRNAs (miRNAs) are key regulators of metabolic diseases, and natural products can improve lipid and glucose metabolism disorders and cardiovascular diseases by regulating the expression of miRNAs. In this review, we present the recent advances involving the associations between miRNAs and natural products and the current evidence showing the positive effects of miRNAs for natural product treatment in metabolic diseases. We also encourage further research to address the relationship between miRNAs and natural products under physiological and pathological conditions, thus leading to stronger support for drug development from natural products in the future.

Cardioprotective effect of curcumin on myocardial ischemia/reperfusion injury: a meta-analysis of preclinical animal studies

Objective: This meta-analysis aimed to determine the efficacy of curcumin in preventing myocardial ischemia/reperfusion (I/R) injury in animal models. Methods: Studies published from inception to January 2023 were systematically searched in databases including PubMed, Web of Science, Embase, China's National Knowledge Infrastructure (CNKI), Wan-Fang database, and VIP database (VIP). The SYRCLE's RoB tool was used to determine methodological quality. Sensitivity analysis and subgroup analysis were performed when there was high heterogeneity. Publication bias was assessed using a funnel plot. Results: Thirty-seven studies involving 771 animals were included in this meta-analysis with methodology quality scores ranging from 4 to 7. The results indicated that curcumin treatment significantly improved myocardial infarction size standard mean difference (SMD) = -5.65; 95% confidence interval (CI): 6.94, -4.36; p < 0.01; I² = 90%). The sensitivity analysis for infarct size showed that the results were stable and reliable. However, the funnel plot was asymmetric. The subgroup analysis included species, animal model, dose, administration, and duration. The results showed that the subgroup dose was statistically significant between subgroups. In addition, curcumin treatment improved cardiac function, myocardial injury enzymes, and oxidative stress levels in animal models of myocardial I/R injury. The funnel plot revealed that there is publication bias for creatine kinase and lactate dehydrogenase. Finally, we performed a meta-analysis of inflammatory cytokines and apoptosis index. The results showed that curcumin treatment downregulated serum inflammatory cytokine levels and myocardial apoptosis index. Conclusion: This meta-analysis suggests that curcumin has excellent potential for the treatment of myocardial I/R injury in animal models. However, this conclusion needs to be further discussed and verified in large animal models and human clinical trials. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42022383901.

AIFM1, negatively regulated by miR-145-5p, aggravates hypoxia-induced cardiomyocyte injury

BACKGROUND

Hypoxia-induced apoptosis is linked to the pathogenesis of myocardial infarction. The role of apoptosis-inducing factor mitochondria associated 1 (AIFM1) in cardiomyocyte injury remains unclear. This study was aimed at probing into the role and the underlying regulatory mechanism of AIFM1 in myocardial injury.

METHODS

H9c2 cardiomyocytes and C57BL/6 mice were used for myocardial hypoxic/ischemic injury and myocardial infarction animal models. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to evaluate the expression levels of AIFM1 mRNA and miR-145-5p. Western blot was used for examining the expression levels of AIFM1, caspase-3, cleaved caspase-3, p-53, and γ-H2AX. Cell viability was examined by cell counting kit-8 (CCK-8) assay and BrdU assay. Interaction between AIFM1 and miR-145-5p was determined by bioinformatics analysis, qRT-PCR, Western blot, and dual-luciferase reporter assay.

RESULTS

AIFM1 expression was markedly highly elevated, while miR-145-5p expression was significantly down-regulated in the myocardial infarction animal model and H9c2 cells under hypoxia. Augmentation of AIFM1 led to a dramatic decrease of cell viability, accompanied by an increase of the secretion of the inflammatory cytokines IL-1β, TNF-α, IL-6, and the expression of cleaved caspase-3. Furthermore, AIFM1 was identified as a target of miR-145-5p. In addition, miR-145-5p/AIFM1 axis regulated the expression of p53.

CONCLUSION

AIFM1 may exacerbate myocardial ischemic injury by promoting inflammation and the injury of cardiomyocytes, and its up-regulation may be partly due to the down-regulation of miR-145-5p.

A "Double-Locked" and Enzyme/pH-Activated Theranostic Agent for Accurate Tumor Imaging and Therapy

Theranostic agents for concurrent cancer therapy and diagnosis have begun attracting attention as a promising modality. However, accurate imaging and identification remains a great challenge for theranostic agents. Here, we designed and synthesized a novel theranostic agent H6M based on the "double-locked" strategy by introducing an electron-withdrawing nitro group into 1-position of a pH-responsive 3-amino-β-carboline and further covalently linking the hydroxamic acid group, a zinc-binding group (ZBG), to the 3-position of β-carboline to obtain histone deacetylase (HDAC) inhibitory effect for combined HDAC-targeted therapy. We found that H6M can be specifically reduced under overexpressed nitroreductase (NTR) to produce H6AQ, which emits bright fluorescence at low pH. Notably, H6M demonstrated a selective fluorescence imaging via successive reactions with NTR (first "key") and pH (second "key"), and precisely identified tumor margins with a high S/N ratio to guide tumor resection. Finally, H6M exerted robust HDAC1/cancer cell inhibitory activities compared with a known HDAC inhibitor SAHA. Therefore, the NTR/pH-activated theranostic agent provided a novel tool for precise diagnosis and efficient tumor therapy.

Pharmacological Mechanisms and Clinical Applications of Curcumin: Update

Curcumin, a well-known hydrophobic polyphenol extracted from the rhizomes of turmeric (Curcuma longa L.), has attracted great interest in the last ten years due to its multiple pharmacological activities. A growing body of evidence has manifested that curcumin has extensive pharmacological activities including anti-inflammatory, anti-oxygenation, lipid regulation, antiviral, and anticancer with hypotoxicity and minor adverse reactions. However, the disadvantages of low bioavailability, short half-life in plasma, low drug concentration in blood, and poor oral absorption severely limited the clinical application of curcumin. Pharmaceutical researchers have carried out plenty of dosage form transformations to improve the druggability of curcumin and have achieved remarkable results. Therefore, the objective of this review summarizes the pharmacological research progress, problems in clinical application and the improvement methods of curcumin's druggability. By reviewing the latest research progress of curcumin, we believe that curcumin has a broad clinical application prospect for its wide range of pharmacological activities with few side effects. The deficiencies of lower bioavailability of curcumin could be improved by dosage form transformation. However, curcumin in the clinical application still requires further study regarding the underlying mechanism and clinical trial verification.

Leonurine Alleviates Hypoxia-Induced Myocardial Damage by Regulating miRNAs

Objective

miRNAs as pharmaco-targets have been investigated in multifarious diseases. Our study aimed to determine whether leonurine was a potential cardioprotective agent by targeting miRNAs in hypoxia-stimulated mice and H9c2 cardiomyocytes.

Methods

Cell proliferation and apoptosis were examined by CCK-8 and TUNEL assay in hypoxia-stimulated rat H9c2 cardiomyocytes. miRNAs expression levels in cardiomyocytes in response to hypoxia stimulation were detected by RT-qPCR. Mice with myocardial injury were induced by chronic intermittent hypoxia stimulation.

Results

Leonurine alleviated hypoxia-induced cardiac hypertrophy in mice. Moreover, up-regulation of miR-31 and down-regulation of miR-210 in hypoxia-stimulated mice were reversed by leonurine administration. Leonurine exhibited cardioprotective activity in an vitro cell model of hypoxia-stimulated rat H9c2 cardiomyocytes, reflecting that the compound improved hypoxia-induced growth inhibition and apoptosis of cardiomyocytes. TUNEL assay revealed that transfection of miR-31 inhibitors or miR-210 mimics abrogated hypoxia-induced cardiomyocyte apoptosis. In contrast to that, miR-31 mimics or miR-210 inhibitors counteracted the anti-apoptotic effect of leonurine on hypoxia-treated rat H9c2 cardiomyocytes.

Conclusion

Our findings suggest that miR-31 and miR-210 as the upstream regulators of leonurine are involved in hypoxia-induced cardiomyocyte apoptosis. Leonurine can target miRNAs to protect against hypoxia-induced myocardial damage. miRNAs as potential drug targets may provide prospective therapeutic strategies for the treatment of myocardial damage.

LncRNA-MIAT promotes neural cell autophagy and apoptosis in ischemic stroke by up-regulating REDD1

BACKGROUND

Ischemic stroke (IS) accounts for 80% of stroke incidence, which has an impact on the life quality of patients. Long non-coding RNA (LncRNA), a class of non-coding transcripts greater than 200 nucleotidesin length, has been extensively studied in cerebrovascular diseases. Myocardial infarction associated transcript (MIAT) is highly expressed in nervous system. Therefore this study aims to explore the role of LncRNA MIAT in IS and to clarify its underlying mechanism, providing therapeutic value for the treatment of IS.

METHODS

The neurological function of rats was evaluated by neurological deficit score. Triphenyltetrazolium chloride (TTC) staining was used to detect infarct area in brain tissues. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to examine the expression of MIAT. Western blotting was used to detect the expressions of REDD1, p-mTOR, autophagy-related proteins LC3 and p62, and apoptotic-related proteins Bax, cleaved-caspase3, Bcl-2. Flow cytometry was applied to examine neuronal cell apoptosis. RNA pull-down and RIP assay was used to verify the binding of MIAT and REDD1. The level of REDD1 ubiquitination was detected by ubiquitination and Co-immunoprecipitation (Co-IP) assay.

RESULTS

The expressions of MIAT and REDD1 were increased in IS rats and oxygen-glucose deprivation/reoxygenation (OGD/R)-induced PC12 cell injury. After interference with si-MIAT, the results of flow cytometry showed that the rate of apoptosis was reduced. Western blotting results showed that the expression of LC3II/LC3I, Bax, and cleaved-caspase3 was decreased, while the expression of p-mTOR, p62, and Bcl-2 was increased. RNA pull-down and RIP assay found the binding relationship between MIAT and REDD1, and interference with si-MIAT down-regulated the expression of REDD1. The level of REDD1 ubiquitination was increased and the expression of REDD1 was decreased after interference with si-MIAT in PC12 cells. Co-IP results showed that interference with si-MIAT enhanced the binding ability of CUL4A-DDB1 and REDD1.

CONCLUSION

Altogether, MIAT promotes autophagy and apoptosis of neural cells and aggravates IS by up-regulating the expression of REDD1.

Curcumin and cardiovascular diseases: Focus on cellular targets and cascades

Cardiovascular diseases (CVDs) are one of the leading causes of the most considerable mortality globally, and it has been tried to find the molecular mechanisms and design new drugs that triggered the molecular target. Curcumin is the main ingredient of Curcuma longa (turmeric) that has been used in traditional medicine for treating several diseases for years. Numerous investigations have indicated the beneficial effect of Curcumin in modulating multiple signaling pathways involved in oxidative stress, inflammation, apoptosis, and proliferation. The cardiovascular protective effects of Curcumin against CVDs have been indicated in several studies. In the current review study, we provided novel information on Curcumin's protective effects against various CVDs and potential molecular signaling targets of Curcumin. Nonetheless, more studies should be performed to discover the exact molecular target of Curcumin against CVDs.

Curcumin Attenuates Hypoxia-Induced Oxidative Neurotoxicity, Apoptosis, Calcium, and Zinc Ion Influxes in a Neuronal Cell Line: Involvement of TRPM2 Channel

Apoptosis/cell death and reactive oxygen species (ROS) via overload free Ca²⁺ and Zn²⁺ uptake into mitochondria are emerging as crucial events in the etiology of hypoxia (HPX)-induced neurodegenerative diseases. The neuroprotective actions of curcumin (CURC) via modulation of oxidative stress and the PARP1-dependent activated TRPM2 cation channel on the ROS generation and cell death in several neurons have been recognized. However, the molecular mechanisms underlying CURC's neuroprotection remain elusive. We investigated the role of CURC via modulation of TRPM2 on cell death and oxidative cytotoxicity in SH-SY5Y neuronal cells. The SH-SY5Y cells were divided into five groups as follows: CURC (10 µM for 24 h), HPX (200 µM CoCl₂ for 24 h), CURC + HPX, and HPX + TRPM2 blockers (2-APB-100 µM or ACA-25 µM for 30 min). In some experiments, the cells in the HPX groups were additionally incubated with PARP1 (PJ34) and Zn²⁺ (TPEN) inhibitors. The exposure of CoCl₂ induced increases of TRPM2 current density and Ca²⁺ fluorescence intensity with an increase of mitochondrial membrane depolarization and ROS generation. When HPX-induced TRPM2 activity was blocked by 2-APB and ACA, or the cells were treated with CURC, the increase of ROS generation, the expression levels of TRPM2 and PARP1 were restored. The levels of apoptosis and cell death in the cells were enriched with increases of caspase-3 and -9 activations, although they were decreased by CURC treatment. HPX-induced increase of cytosolic Zn²⁺ was attenuated by the TPEN and CURC treatments. In conclusion, CURC attenuates HPX-induced mitochondrial ROS generation, apoptosis, cell death, and TRPM2-mediated Ca²⁺ signaling and may provide an avenue for treating HPX-induced neurological diseases associated with the ROS, Ca²⁺, and Zn²⁺.

Phenolic Compounds Exerting Lipid-Regulatory, Anti-Inflammatory and Epigenetic Effects as Complementary Treatments in Cardiovascular Diseases

Atherosclerosis is the main process behind cardiovascular diseases (CVD), maladies which continue to be responsible for up to 70% of death worldwide. Despite the ongoing development of new and potent drugs, their incomplete efficacy, partial intolerance and numerous side effects make the search for new alternatives worthwhile. The focus of the scientific world turned to the potential of natural active compounds to prevent and treat CVD. Essential for effective prevention or treatment based on phytochemicals is to know their mechanisms of action according to their bioavailability and dosage. The present review is focused on the latest data about phenolic compounds and aims to collect and correlate the reliable existing knowledge concerning their molecular mechanisms of action to counteract important risk factors that contribute to the initiation and development of atherosclerosis: dyslipidemia, and oxidative and inflammatory-stress. The selection of phenolic compounds was made to prove their multiple benefic effects and endorse them as CVD remedies, complementary to allopathic drugs. The review also highlights some aspects that still need clear scientific explanations and draws up some new molecular approaches to validate phenolic compounds for CVD complementary therapy in the near future.

Inhibitor 1 of Protein Phosphatase 1 Regulates Ca2+/Calmodulin-Dependent Protein Kinase II to Alleviate Oxidative Stress in Hypoxia-Reoxygenation Injury of Cardiomyocytes

Ca²⁺/calmodulin-dependent protein kinase II (CaMKII), regulated by inhibitor 1 of protein phosphatase 1 (I1PP1), is vital for maintaining cardiovascular homeostasis. However, the role and mechanism of I1PP1 against hypoxia-reoxygenation (H/R) injury in cardiomyocytes remain a question. In our study, after I1PP1 overexpression by adenovirus infection in the neonatal cardiomyocytes followed by hypoxia for 4 h and reoxygenation for 12 h, the CaMKIIδ alternative splicing subtype, ATP content, and lactate dehydrogenase (LDH) release were determined. CaMKII activity was evaluated by phosphoprotein phosphorylation at Thr17 (p-PLB Thr17), CaMKII phosphorylation (p-CaMKII), and CaMKII oxidation (ox-CaMKII). Reactive oxygen species (ROS), mitochondrial membrane potential, dynamin-related protein 1 (DRP1), and optic atrophy 1 (OPA1) expressions were assessed. Our study verified that I1PP1 overexpression attenuated the CaMKIIδ alternative splicing disorder; suppressed PLB phosphorylation at Thr17, p-CaMKII, and ox-CaMKII; decreased cell LDH release; increased ATP content; attenuated ROS production; increased mitochondrial membrane potential; and decreased DRP1 expression but increased OPA1 expression in the cardiomyocytes after H/R. Contrarily, CaMKIIδ alternative splicing disorder, LDH release, ATP reduction, and ROS accumulation were aggravated after H/R injury with the I1PP1 knockdown. Collectively, I1PP1 overexpression corrected disorders of CaMKIIδ alternative splicing, inhibited CaMKII phosphorylation, repressed CaMKII oxidation, suppressed ROS production, and attenuated cardiomyocyte H/R injury.

Curcumin ameliorates glyoxylate-induced calcium oxalate deposition and renal injuries in mice

BACKGROUND

Nephrolithiasis is one of the most common and frequent urologic diseases worldwide. Several pathophysiological mechanisms are involved in stone formation, including oxidative stress, inflammation, apoptosis, fibrosis and autophagy. Curcumin, the predominant active component of turmeric, has been shown to have pleiotropic biological and pharmacological properties, such as antioxidant, anti-inflammatory and antifibrotic effects.

PURPOSE

The current study proposed to systematically investigate the protective effects and the underlying mechanisms of curcumin in a calcium oxalate (CaOx) nephrolithiasis mouse model.

METHODS

The animal model was established in male C57BL/6 mice by successive intraperitoneal injection of glyoxylate (100 mg/kg) for 1 week. Curcumin was orally given to mice 7 days before the injection of glyoxylate and for a total of 14 days at 50 mg/kg or 100 mg/kg. Bilateral renal tissue was harvested and processed for oxidative stress index detection, histopathological examinations and other analyses.

RESULTS

Coadministration of curcumin could significantly reduce glyoxylate-induced CaOx deposition and simultaneous tissue injury in mouse kidneys. Meanwhile, curcumin alleviated the oxidative stress response via reducing MDA content and increasing SOD, CAT, GPx, GR and GSH levels in this animal model. Moreover, treatment with curcumin significantly inhibited apoptosis and autophagy induced by hyperoxaluria. Curcumin also attenuated the high expression of IL-6, MCP-1, OPN, CD44, α-SMA, Collagen I and collagen fibril deposition, which were elevated by hyperoxaluria. Furthermore, the results revealed that both the total expression and nuclear accumulation of Nrf2, as well as its main downstream products such as HO-1, NQO1 and UGT, were decreased in the kidneys of mice in the crystal group, while treatment with curcumin could rescue this deterioration.

CONCLUSION

Curcumin could significantly alleviate CaOx crystal deposition in the mouse kidney and the concurrent renal tissue injury. The underlying mechanism involved the combination of antioxidant, anti-apoptotic, inhibiting autophagy, anti-inflammatory, and antifibrotic activity and the ability to decrease expression of OPN and CD44 through the Nrf2 signaling pathway. The pleiotropic antilithic properties, combined with the minimal side effects, make curcumin a good potential choice to prevent and treat new or recurrent nephrolithiasis.

miRNA-7a-2-3p Inhibits Neuronal Apoptosis in Oxygen-Glucose Deprivation (OGD) Model

Neuronal apoptosis is a major pathological hallmark of the neonatal hypoxic-ischemic brain damage (HIBD); however, the role of miR-7a-2-3p in the regulation of HIBD remains unknown. The purpose of this study was to explore the possible roles of miR-7a-2-3p in brain injury using a hypoxia-ischemia model in rats and oxygen-glucose deprivation (OGD) model in vitro. Firstly, we established the hypoxia-ischemia (HI) model and verified the model using Zea Longa scores and MRI in rats. Next, the changes of miR-7a-2-3p were screened in the ischemic cortex of neonatal rats by qRT-PCR at 12, 48, and 96 h after HIBD. We have found that the expression of miR-7a-2-3p in the HI rats decreased significantly, compared with the sham group (P < 0.01). Then, we established the OGD model in PC12 cells, SH-SY5Y cells and primary cortical neurons in vitro and qRT-PCR was used to confirm the changes of miR-7a-2-3p in these cells after the OGD. In order to determine the function of miR-7a-2-3p, PC12 cells, SH-SY5Y cells and rat primary cortical neurons were randomly divided into normal, OGD, mimic negative control (mimic-NC) and miR-7a-2-3p groups. Then, Tuj1+ (neuronal marker) staining, TUNEL assay (to detect apoptotic cells) and MTT assay (to investigate cell viability) were performed. We have found that the number of PC12 cells, SH-SY5Y cells and cortical neurons in the miR-7a-2-3p groups increased significantly (P < 0.01) in comparison to the OGD groups. The survival of cortical neurons in the miR-7a-2-3p group was improved markedly (P < 0.01), while the apoptosis of neurons in the miR-7a-2-3p group was significantly decreased (P < 0.01), compared with the normal group. Lastly, we investigated the target genes of miR-7a-2-3p by using the prediction databases (miRDB, TargetScan, miRWalk, and miRmap) and verified the target genes with qRT-PCR in the HI rats. Bioinformatics prediction showed that Vimentin (VIM), pleiomorphic adenoma gene 1(PLAG1), dual specificity phosphatase 10 (DUSP10), NAD(P)H dehydrogenase, quinone 1 (NQO1) and tumor necrosis factor receptor superfamily member 1B (TNFRSF1B) might be the targets of miR-7a-2-3p and the qRT-PCR confirmed that VIM increased in the HI rats (P < 0.01). In conclusion, miR-7a-2-3p plays a crucial role in the hypoxic-ischemic injury, and is associated with regulation of VIM.

Cellular and molecular mechanisms of curcumin in prevention and treatment of disease

Curcumin is a naturally occurring polyphenolic compound present in rhizome of Curcuma longa belonging to the family zingiberaceae. Growing experimental evidence revealed that curcumin exhibit multitarget biological implications signifying its crucial role in health and disease. The current review highlights the recent progress and mechanisms underlying the wide range of pharmacological effects of curcumin against numerous diseases like neuronal, cardiovascular, metabolic, kidney, endocrine, skin, respiratory, infectious, gastrointestinal diseases and cancer. The ability of curcumin to modulate the functions of multiple signal transductions are linked with attenuation of acute and chronic diseases. Numerous preclinical and clinical studies have revealed that curcumin modulates several molecules in cell signal transduction pathway including PI3K, Akt, mTOR, ERK5, AP-1, TGF-β, Wnt, β-catenin, Shh, PAK1, Rac1, STAT3, PPARγ, EBPα, NLRP3 inflammasome, p38MAPK, Nrf2, Notch-1, AMPK, TLR-4 and MyD-88. Curcumin has a potential to prevent and/or manage various diseases due to its anti-inflammatory, anti-oxidant and anti-apoptotic properties with an excellent safety profile. In contrast, the anti-cancer effects of curcumin are reflected due to induction of growth arrest and apoptosis in various premalignant and malignant cells. This review also carefully emphasized the pharmacokinetics of curcumin and its interaction with other drugs. Clinical studies have shown that curcumin is safe at the doses of 12 g/day but exhibits poor systemic bioavailability. The use of adjuvant like piperine, liposomal curcumin, curcumin nanoparticles and curcumin phospholipid complex has shown enhanced bioavailability and therapeutic potential. Further studies are warranted to prove the potential of curcumin against various ailments.

Protective effects and mechanism of curcumin on myocardial injury induced by coronary microembolization

OBJECTIVE

Coronary microembolization (CME) is a common complication during the percutaneous coronary intervention (PCI). CME-induced local myocardial inflammation and myocardial apoptosis are the primary causes of progressive cardiac dysfunction. Curcumin exerts a protective role in various cardiovascular diseases; however, its effects in CME are yet to be clarified. Therefore, the current study investigated the effects of curcumin on myocardial inflammatory responses, myocardial apoptosis, and cardiac dysfunctions induced by CME in rats.

METHODS

A total of 40 Sprague-Dawley rats were randomly divided into the following groups: Sham operation (sham group), CME group, curcumin, and control with 10 rats in each group. The ascending aortas were clamped, and the CME-model group was established by injecting microspheres into the apex of the left ventricle. An equivalent amount of normal saline was injected to establish the sham group. The cardiac functions, serum c-troponin I level, and apoptotic index was examined. Also, the levels of Toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MYD88), nuclear factor κB (NF-κB) p65, BCL2-associated X protein (Bax), B-cell lymphoma 2 (Bcl-2), cleaved caspase-3, tumor necrosis factor α (TNF-α), and interleukin-1β (IL-1β) were detected.

RESULTS

Myocardial dysfunction enhanced serum c-troponin I, and apoptotic index were induced following CME. Moreover, CME elevated the expression of TLR4, MyD88, NF-κB p65, cleaved caspase-3, TNF-α, and IL-1β, while the Bcl-2/Bax ratio decreased. Curcumin reversed these effects by CME, while the gastric lavage control did not exert any effect.

CONCLUSION

Curcumin was responsible for the anti-CME-induced myocardial injury. The effector mechanism might be related to the reduction of cardiomyocyte apoptosis and inhibition of myocardial inflammatory responses mediated by TLR4/MyD88/NF-κB signaling pathway.

Paclitaxel alleviated liver injury of septic mice by alleviating inflammatory response via microRNA-27a/TAB3/NF-κB signaling pathway

Excessive inflammatory response and apoptosis play an important role in the sepsis-induced liver injury. Paclitaxel, a diterpene alkaloid of Taxus brevifolia, is widely used as an anti-tumor drug and shows protective effects on acute lung and kidney injury. However, whether it has a protective effect against sepsis-induced liver injury has not been reported. The objective of this study was to investigate the protective effects of paclitaxel in septic liver injury in mice and associated molecular mechanisms. Our results showed that paclitaxel treatment improved LPS-induced liver injury, as evidenced by the reduced aminotransferase activity, histological scores and apoptosis in the liver tissues. This was accompanied by the alleviating of inflammation and oxidative stress, such as decreased levels of tumor necrosis factor alpha (TNF-α), interleukin-1 (IL-6) interleukin-1β (IL-1β) and malondialdehyde (MDA) and increased levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-px) in serum and liver tissues. Subsequent microarray and qRT-PCR analysis further showed that miR-27a was significantly decreased in mice with sepsis, which was recovered by paclitaxel pretreatment. Antagomir-miR-27a suppressed the therapeutic effects of paclitaxel in mice liver injury model via promoting inflammatory response. Of note, TAB3, which participated in the activation of the NF-κB signaling pathway, was identified as a direct target of miR-27 by luciferase reporter gene assays. Then, we revealed a reverse relationship between miR-27a expression levels and TAB3 mRNA levels in liver tissues from septic mice. Furthermore, paclitaxel treatment significantly decreased the expression of NF-κB p65, but increased inhibitor of nuclear factor-κB-α (IκBα) protein levels in septic mice, suggesting the inactivation of NF-κB signaling pathway. Notably, the inhibitory effects of paclitaxel on NF-κB signaling pathway were reversed by antagomir-miR-27a. Our data indicated that paclitaxel significantly attenuated septic induced liver injury through reducing inflammatory response via miR-27a/TAB3/NF-κB signaling pathway.

Protective Effect of Tempol Against Hypoxia-Induced Oxidative Stress and Apoptosis in H9c2 Cells

Background

Hypoxia-induced oxidant stress and cardiomyocyte apoptosis are considered essential processes in the progression of heart failure. Tempol is a nitroxide compound that scavenges many reactive oxygen species (ROS) and has antioxidant and cardioprotective effects. This study aimed to investigate the protective effect of Tempol against hypoxia-induced oxidative stress and apoptosis in the H9c2 rat cardiomyoblast cell line, in addition to related mechanisms.

Material/Methods

H9c2 cells were pre-treated with Tempol, followed by hypoxia (37°C, 5% CO₂, and 95% N₂) for 24 h. Cell viability was detected using MTT assay. ROS level was evaluated using DCFH-DA. Lactate dehydrogenase (LDH), creatinine kinase (CK), malondialdehyde (MDA), catalase (CAT), and superoxide dismutase (SOD) were evaluated using the relevant kits. Cell apoptosis was determined by Annexin V/7-AAD double labelling. The expression of apoptosis-related molecules was assessed with RT-PCR analysis and Western blotting.

Results

Tempol protected H9c2 cells against hypoxia-induced injury, with characteristics of increased the cell viability and reduced LDH and CK release. Tempol also reduced oxidant stress by inhibiting ROS generation and lipid peroxidation, as well as enhancing antioxidant enzyme activity. Moreover, Tempol pretreatment upregulated the expression of Bcl-2 and downregulated the expression of Bax and caspase-3, thereby reducing hypoxia-induced apoptosis in H9c2 cells.

Conclusions

These results indicate that Tempol reduces the hypoxia-induced oxidant stress and apoptosis in H9c2 cells by scavenging free radicals and modulating the expression of apoptosis-related proteins.