Galangin Attenuates Isoproterenol-Induced Inflammation and Fibrosis in the Cardiac Tissue of Albino Wistar Rats

Compound 3K attenuates isoproterenol-induced cardiac hypertrophy by inhibiting pyruvate kinase M2 (PKM2) pathway

AIM

Chronic sympathetic stimulation has been identified as a primary factor in the pathogenesis of cardiac hypertrophy (CH). However, there is no appropriate treatment available for the management of CH. Recently, it has been revealed that pyruvate kinase M2 (PKM2) plays a significant role in cardiac remodeling, fibrosis, and hypertrophy. However, the therapeutic potential of selective PKM2 inhibitor has not yet been explored in cardiac hypertrophy. Thus, in the current study, we have studied the cardioprotective potential of Compound 3K, a selective PKM2 inhibitor in isoproterenol-induced CH model.

METHODS

To induce cardiac hypertrophy, male Wistar rats were subcutaneously administered isoproterenol (ISO, 5 mg/kg/day) for 14 days. Compound 3K at dosages of 2 and 4 mg/kg orally was administered to ISO-treated rats for 14 days to explore its effects on various parameters like ECG, ventricular functions, hypertrophic markers, histology, inflammation, and protein expression were performed.

RESULTS

Fourteen days administration of ISO resulted in the induction of CH, which was evidenced by alterations in ECG, ventricular dysfunctions, increase in hypertrophy markers, and fibrosis. The immunoblotting of hypertrophy heart revealed the significant rise in PKM2 and reduction in PKM1 protein expression. Treatment with Compound 3K led to downregulation of PKM2 and upregulation of PKM1 protein expression. Compound 3K showed cardioprotective effects by improving ECG, cardiac functions, hypertrophy markers, inflammation, and fibrosis. Further, it also reduced cardiac expression of PKM2-associated splicing protein, HIF-1α, and caspase-3.

CONCLUSION

Our findings suggest that Compound 3K has a potential cardioprotective effect via PKM2 inhibition in isoproterenol-induced CH.

Comprehensive and critical view on the anti-inflammatory and immunomodulatory role of natural phenolic antioxidants

The immune response encompasses innate and adaptive immunity, each with distinct and specific activities. The innate immune system is constituted by phagocytic cells, macrophages, monocytes and neutrophils, the cascade system, and different classes of receptors such as toll-like receptors that are exploited by the innate immune cells. The adaptive immune system is antigen-specific, encompassing memory lymphocytes and the corresponding specific receptors. Inflammation is understood as an activation of different signaling pathways such as toll-like receptors or nuclear factor kappa-light-chain-enhancer of activated B cells, with an increase in nitric oxide, inflammatory cytokines and chemokines. Increased oxidative stress has been identified as main source of chronic inflammation. Phenolic antioxidants modulate the activities of lymphocytes and macrophages by impacting cytokines and nitric oxide release, exerting anti-inflammatory effect. The nuclear-factor kappa-light-chain-enhancer of activated B cells signaling pathway and the mitogen-activated protein kinase pathway are targeted, alongside an increase in nuclear factor erythroid 2-related factor mediated antioxidant response, triggering the activity of antioxidant enzymes. The inhibitive potential on phospholipase A2, cyclooxygenase and lipoxygenase in the arachidonic acid pathway, and the subsequent reduction in prostaglandin and leukotriene generation, reveals the potential of phenolics as inflammation antagonists. The immunomodulative potential encompasses the capacity to interfere with proinflammatory cytokine synthesis and with the expression of the corresponding genes. A diet rich in antioxidants can result in prevention of inflammation-related pathologies. More investigations are necessary to establish the role of these antioxidants in therapy. The appropriate delivery system and the prooxidant effects exhibited at large doses, or in the presence of heavy metal cations should be regarded.

Galangin: A food-derived flavonoid with therapeutic potential against a wide spectrum of diseases

Galangin is an important flavonoid with natural activity, that is abundant in galangal and propolis. Currently, various biological activities of galangin have been disclosed, including anti-inflammation, antibacterial effect, anti-oxidative stress and aging, anti-fibrosis, and antihypertensive effect. Based on the above bioactivities, more and more attention has been paid to the role of galangin in neurodegenerative diseases, rheumatoid arthritis, osteoarthritis, osteoporosis, skin diseases, and cancer. In this paper, the natural sources, pharmacokinetics, bioactivities, and therapeutic potential of galangin against various diseases were systematically reviewed by collecting and summarizing relevant literature. In addition, the molecular mechanism and new preparation of galangin in the treatment of related diseases are also discussed, to broaden the application prospect and provide reference for its clinical application. Furthermore, it should be noted that current toxicity and clinical studies of galangin are insufficient, and more evidence is needed to support its possibility as a functional food.

Pharmacological activities and therapeutic potential of galangin, a promising natural flavone, in age-related diseases

BACKGROUND

The extension of average life expectancy and the aggravation of population aging have become the inevitable trend of human development. In an aging society, various problems related to medical care for the elderly have become increasingly prominent. However, most of the age-related diseases have the characteristics of multiple diseases at the same time, prone to complications, and atypical clinical manifestations, which bring great difficulties to its treatment. Galangin (3,5,7-trihydroxyflavone) is a natural active compound extracted from the root of Alpinia officinarum Hance (Zingiberaceae). Recently, many studies have shown that galangin has potential advantages in the treatment of neurodegenerative diseases and cardiovascular and cerebrovascular diseases, which are common in the elderly. In addition, it also showed that galangin had prospective activities in the treatment of tumor, diabetes, liver injury, asthma and arthritis.

PURPOSE

This review aims to systematically summarize and discuss the effects and the underlying mechanism of galangin in the treatment of age-related diseases.

METHODS

We searched PubMed, SciFinder, Web of Science and CNKI literature database resources, combined with the keywords "galangin", "neurodegenerative disease", "tumor", "diabetes", "pharmacological activity", "drug combination", "pharmacokinetics", "drug delivery system" and "safety", and comprehensively reviewed the pharmacological activities and mechanism of galangin in treating age-related diseases.

RESULTS

According to the previous studies on galangin, the anti-neurodegenerative activity, cardiovascular and cerebrovascular protective activity, anti-tumor activity, anti-diabetes activity, anti-arthritis activity, hepatoprotective activity and antiasthmatic activity of galangin were discussed, and the related mechanisms were classified and summarized in detail. In addition, the drug combination, pharmacokinetics, drug delivery system and safety of galangin were furtherly discussed.

CONCLUSIONS

This review will provide reference for galangin in the treatment of age-related diseases. Meanwhile, further experimental research and long-term clinical trials are needed to determine the therapeutic safety and efficacy of galangin.

Protective Effects of 2-Methoxyestradiol on Acute Isoproterenol-Induced Cardiac Injury in Rats

Myocardial injury (MI) is an important pathological driver of mortality worldwide., and arises as a result of imbalances between myocardial oxygen demand and supply. In MI, oxidative stress often leads to inflammatory changes and apoptosis. Current therapies for MI are known to cause various adverse effects. Consequently, the development of new therapeutic agents with a reduced adverse event profile is necessary. In this regard, 2-methoxyestradiol (2ME), the metabolic end-product of oestradiol, possesses anti-inflammatory and antioxidant properties. The aim of this research is to assess the impact of 2ME on cardiac injury caused by isoproterenol (ISO) in rats. Animals were separated into six groups; controls, and those receiving 2ME (1 mg/kg), ISO (85 mg/kg), ISO + 2ME (0.25 mg/kg), ISO + 2ME (0.5 mg/kg), and ISO + 2ME (1 mg/kg). 2ME significantly attenuated ISO-induced changes in electrocardiographic changes and the cardiac histological pattern. This compound also decreased lactate dehydrogenase activity, creatine kinase myocardial band and troponin levels. The ability of 2ME to act as an antioxidant was shown by a decrease in malondialdehyde concentration, and the restoration of glutathione levels and superoxide dismutase activity. Additionally, 2ME antagonized inflammation and cardiac cell apoptosis, a process determined to be mediated, at least partially, by suppression of Gal-3/TLR4/MyD88/NF-κB signaling pathway. 2ME offers protection against acute ISO-induced MI in rats and offers a novel therapeutic management option.

Preventive Effect of 6-shogaol on D-galactosamine Induced Hepatotoxicity Through NF-?B/MAPK Signaling Pathway in Rats

This analysis aims to see whether 6-shogaol could protect rats against D-galactosamine (D-GalN)-induced Hepatotoxicity. The Wistar rats were divided into four groups (n=6). Group 1 received a standard diet, Group 2 received an oral administration of 6-shogaol (20 mg/kg b.wt), Group 3 received an intraperitoneal injection of D-GalN (400 mg/kg b.wt) on 21st day, and Group 4 received an oral administration of 6-shogaol (20mg/kg b.wt) for 21 days and D-GalN (400 mg/kg b.wt) injection only on 21st day. The hepatic marker enzymes activity, lipid peroxidative markers level increased significantly and antioxidant activity/level significantly reduced in D-GalN-induced rats. 6-shogaol Pretreatment effectively improves the above changes in D-GalN-induced rats. Further, inflammatory marker expression and MAPK signaling molecules were downregulated by 6-shogaol. These findings showed that 6-shogaol exerts hepatoprotective effects via the enhanced antioxidant system and attenuated the inflammation and MAPK signaling pathway in D-GalN-induced rats.

Galangin Attenuates Myocardial Ischemic Reperfusion-Induced Ferroptosis by Targeting Nrf2/Gpx4 Signaling Pathway

Purpose

Myocardial ischemic reperfusion injury (MIRI) is a crucial clinical problem globally. The molecular mechanisms of MIRI need to be fully explored to develop new therapeutic methods. Galangin (Gal), which is a natural flavonoid extracted from Alpinia Officinarum Hance and Propolis, possesses a wide range of pharmacological activities, but its effects on MIRI remain unclear. This study aimed to determine the pharmacological effects of Gal on MIRI.

Methods

C57BL/6 mice underwent reperfusion for 3 h after 45 min of ischemia, and neonatal rat cardiomyocytes (NRCs) subjected to hypoxia and reoxygenation (HR) were cultured as in vivo and in vitro models. Echocardiography and TTC-Evans Blue staining were performed to evaluate the myocardial injury. Transmission electron microscope and JC-1 staining were used to validate the mitochondrial function. Additionally, Western blot detected ferroptosis markers, including Gpx4, FTH, and xCT.

Results

Gal treatment alleviated cardiac myofibril damage, reduced infarction size, improved cardiac function, and prevented mitochondrial injury in mice with MIRI. Gal significantly alleviated HR-induced cell death and mitigated mitochondrial membrane potential reduction in NRCs. Furthermore, Gal significantly inhibited ferroptosis by preventing iron overload and lipid peroxidation, as well as regulating Gpx4, FTH, and xCT expression levels. Moreover, Gal up-regulated nuclear transcriptive factor Nrf2 in HR-treated NRCs. Nrf2 inhibition by Brusatol abolished the protective effect of Gal against ferroptosis.

Conclusion

This study revealed that Gal alleviates myocardial ischemic reperfusion-induced ferroptosis by targeting Nrf2/Gpx4 signaling pathway.

Galangin alleviated myocardial ischemia-reperfusion injury by enhancing autophagic flux and inhibiting inflammation

Autophagy is critically involved in myocardial ischemia-reperfusion (I/R). Autophagy inhibition exacerbates myocardial I/R injury. Few effective agents target autophagy to prevent myocardial I/R injury. Effective drugs that promote autophagy in myocardial I/R warrant further investigation. Galangin (Gal) enhances autophagy and alleviates I/R injury. Here we conducted both in vivo and in vitro experiments to observe the changes in autophagy after galangin treatment and investigated the cardioprotective effects of galangin on myocardial I/R.

METHODS

After 45-min occlusion of the left anterior descending coronary artery, myocardial I/R was induced by slipknot release. One day before surgery and immediately after surgery, the mice were injected intraperitoneally with the same volume of saline or Gal. The effects of Gal were evaluated using echocardiography, 2,3,5-triphenyltetrazolium chloride staining (TTC staining), western blotting, and transmission electron microscopy. Primary cardiomyocytes and bone marrow-derived macrophages were extracted in vitro to measure the cardioprotective effects of Gal.

RESULTS

Compared with the saline-treated group, Gal significantly improved cardiac function and limited infarct enlargement after myocardial I/R. In vivo and in vitro studies demonstrated that Gal treatment promoted autophagy during myocardial I/R. The anti-inflammatory effects of Gal were validated in bone marrow-derived macrophages. These results strongly suggest that Gal treatment can attenuate myocardial I/R injury.

CONCLUSION

Our data demonstrated that Gal could improve left ventricular ejection fraction and reduce infarct size after myocardial I/R by promoting autophagy and inhibiting inflammation.

Galangin as an inflammatory response modulator: An updated overview and therapeutic potential

Numerous chronic diseases, such as cancer, diabetes, rheumatoid arthritis, cardiovascular disease, and gastrointestinal disorders, all have an inflammation-based etiology. In cellular and animal models of inflammation, flavonols were used to show potent anti-inflammatory activity. The flavonols enhanced the synthesis of the anti-inflammatory cytokines transforming growth factor and interleukin-10 (IL-10) and reduced the synthesis of the prostaglandins IL-6, tumor necrosis factor-alpha (TNF-α), and prostaglandin E2 (PGE2), IL-1. Galangin (GAL), a natural flavonol, has a strong ability to control apoptosis and inflammation. GAL was discovered to suppress extracellular signal-regulated kinase (ERK) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB)p65 phosphorylation, which results in anti-inflammatory actions. Arthritis, inflammatory bronchitis, stroke, and cognitive dysfunction have all been treated with GAL. The current review aimed to demonstrate the anti-inflammatory properties of GAL and their protective effects in treating various chronic illnesses, including those of the heart, brain, skin, lungs, liver, and inflammatory bowel diseases.

Galangin Mitigates DOX-induced Cognitive Impairment in Rats: Implication of NOX-1/Nrf-2/HMGB1/TLR4 and TNF-α/MAPKs/RIPK/MLKL/BDNF

The cognitive and behavioral decline observed in cancer survivors who underwent doxorubicin (DOX)-based treatment raises the need for therapeutic interventions to counteract these complications. Galangin (GAL) is a flavonoid-based phytochemical with pronounced protective effects in various neurological disorders. However, its impact on DOX-provoked neurotoxicity has not been clarified. Hence, the current investigation aimed to explore the ability of GAL to ameliorate DOX-provoked chemo-brain in rats. DOX (2mg/kg, once/week, i.p.) and GAL (50mg/kg, 5 times/week., via gavage) were administered for four successive weeks. The MWM and EPM tests were used to evaluate memory disruption and anxiety-like behavior, respectively. Meanwhile, targeted biochemical markers and molecular signals were examined by the aid of ELISA, Western blotting, and immune-histochemistry. In contrast to DOX-impaired rats, GAL effectively preserved hippocampal neurons, improved cognitive/behavioral functions, and enhanced the expression of the cell repair/growth index and BDNF. The antioxidant feature of GAL was confirmed by the amelioration of MDA, NO and NOX-1, along with restoring the Nrf-2/HO-1/GSH cue. In addition, GAL displayed marked anti-inflammatory properties as verified by the suppression of the HMGB1/TLR4 nexus and p-NF-κB p65 to inhibit TNF-α, IL-6, IL-1β, and iNOS. This inhibitory impact extended to entail astrocyte activation, as evidenced by the diminution of GFAP. These beneficial effects were associated with a notable reduction in p-p38^MAPK, p-JNK1/2, and p-ERK1/2, as well as the necroptosis cascade p-RIPK1/p-RIPK3/p-MLKL. Together, these pleiotropic protective impacts advocate the concurrent use of GAL as an adjuvant agent for managing DOX-driven neurodegeneration and cognitive/behavioral deficits. DATA AVAILABILITY: The authors confirm that all relevant data are included in the supplementary materials.

A Possible Novel Protective Effect of Piceatannol against Isoproterenol (ISO)-Induced Histopathological, Histochemical, and Immunohistochemical Changes in Male Wistar Rats

Dry mouth is characterized by lower saliva production and changes in saliva composition. In patients with some salivary gland function remaining, pharmaceutical treatments are not recommended; therefore, new, more effective methods of promoting saliva production are needed. Hence, this study aimed to provide an overview of the histological changes in the salivary gland in the model of isoproterenol (ISO)-induced degenerative changes in male Wistar rats and to evaluate the protective effect of piceatannol. Thirty-two male Wistar rats were randomly divided into four groups: the control group, the ISO group, and the piceatannol (PIC)-1, and -2 groups. After the third day of the experiment, Iso (0.8 mg/100 g) was injected intraperitoneally (IP) twice daily into the animals. PIC was given IP in different daily doses (20 and 40 mg/kg) for three days before ISO and seven days with ISO injection. The salivary glands were rapidly dissected and processed for histological, histochemical, immunohistochemical (Ki-67), and morphometric analysis. Upon seven days of treatment with ISO, marked hypertrophy was observed, along with an increased number of positive Ki-67 cells. Proliferation was increased in some endothelial cells as well as in ducts themselves. Despite the significant decrease in proliferation activity, the control group did not return to the usual activity level after treatment with low-dose PIC. Treatment with a high dose of PIC reduced proliferative activity to the point where it was substantially identical to the results seen in the control group. An ISO-driven xerostomia model showed a novel protective effect of piceatannol. A new era of regenerative medicine is dawning around PIC’s promising role.

D, Banerjee SK, Konar A, Bandyopadhyay A. Downregulation of PTEN Promotes Autophagy via Concurrent Reduction in Apoptosis in Cardiac Hypertrophy in PPAR α−/− Mice

Cardiac hypertrophy is characterized by an increase in the size of the cardiomyocytes which is initially triggered as an adaptive response but ultimately becomes maladaptive with chronic exposure to different hypertrophic stimuli. Prolonged cardiac hypertrophy is often associated with mitochondrial dysfunctions and cardiomyocyte cell death. Peroxisome proliferator activated receptor alpha (PPAR α), which is critical for mitochondrial biogenesis and fatty acid oxidation, is down regulated in hypertrophied cardiomyocytes. Yet, the role of PPAR α in cardiomyocyte death is largely unknown. To assess the role of PPAR α in chronic hypertrophy, isoproterenol, a β-adrenergic receptor agonist was administered in PPAR α knock out (PPAR α−/−) mice for 2 weeks and hypertrophy associated changes in cardiac tissues were observed. Echocardiographic analysis ensured the development of cardiac hypertrophy and compromised hemodynamics in PPAR α−/− mice. Proteomic analysis using high resolution mass spectrometer identified about 1,200 proteins enriched in heart tissue. Proteins were classified according to biological pathway and molecular functions. We observed an unexpected down regulation of apoptotic markers, Annexin V and p53 in hypertrophied heart tissue. Further validation revealed a significant down regulation of apoptosis regulator, PTEN, along with other apoptosis markers like p53, Caspase 9 and c-PARP. The autophagy markers Atg3, Atg5, Atg7, p62, Beclin1 and LC3 A/B were up regulated in PPAR α−/− mice indicating an increase in autophagy. Similar observations were made in a high cholesterol diet fed PPAR α−/−mice. The results were further validated in vitro using NRVMs and H9C2 cell line by blocking PPAR α that resulted in enhanced autophagosome formation upon hypertrophic stimulation. The results demonstrate that in the absence of PPAR α apoptotic pathway is inhibited while autophagy is enhanced. The data suggest that PPAR α signaling might act as a molecular switch between apoptosis and autophagy thereby playing a critical role in adaptive process in cardiac hypertrophy.

Mechanisms and Molecular Targets of Compound Danshen Dropping Pill for Heart Disease Caused by High Altitude Based on Network Pharmacology and Molecular Docking

Compound Danshen dropping pill (CDDP), a famous Chinese medicine formula, has been widely used to treat high-altitude heart disease in China. However, its molecular mechanisms, potential targets, and bioactive ingredients remain elusive. In this study, network pharmacology, molecular docking, and validation experiments were combined to investigate the effective active ingredients and molecular mechanisms of CDDP in the treatment of high-altitude heart disease. Tan IIA may be the main active component of CDDP in the treatment of high-altitude heart disease via HIF-1/PI3K/Akt pathways.

Effect of chronic alcohol consumption on myocardial apoptosis in the rat model of isoproterenol-induced myocardial injury and investigation on the cardioprotective role of calpain inhibitor 1

We investigated the presence of myocardial apoptosis on isoproterenol (ISO)-induced myocardial injury (MI) after long-term high dose alcohol consumption and examined the antiapoptotic role of calpain inhibitor 1. Male Wistar Albino rats (n = 108) were divided into six groups: Control, alcohol (ethanol was given during 30 days for chronic alcohol consumption), MI (150 mg/kg ISO injection at last two days of alcohol consumption), alcohol + MI, alcohol + MI + calpain inhibitor 1 (10 mg/kg inhibitor was injected at 15 min before ISO injections) and Dimethyl Sulfoxide (DMSO) groups. Biochemical, histological, and morphometric methods determined apoptosis levels in the heart tissue of rats. Cytochrome c, caspase 3, and calpain levels were significantly high in alcohol, MI, and alcohol + MI groups. In contrast, mitochondrial cardiolipin content was found to be low in alcohol, MI, and alcohol + MI groups. These parameters were close to the control group in the therapy group. Histological and morphometric data have supported biochemical results. As a result of our biochemical data, myocardial apoptosis was seen in the alcohol, MI, and especially alcohol after MI groups. Calpain inhibitor 1 reduced apoptotic cell death and prevented myocardial tissue injury in these groups. The efficiency of calpain inhibitor was very marked in MI after long-term high dose alcohol consumption.

Canonical transient receptor potential channels and their modulators: biology, pharmacology and therapeutic potentials

Canonical transient receptor potential channels (TRPCs) are nonselective, high calcium permeability cationic channels. The TRPCs family includes TRPC1, TRPC2, TRPC3, TRPC4, TRPC5, TRPC6, and TRPC7. These channels are widely expressed in the cardiovascular and nervous systems and exist in many other human tissues and cell types, playing several crucial roles in the human physiological and pathological processes. Hence, the emergence of TRPCs modulators can help investigate these channels’ applications in health and disease. It is worth noting that the TRPCs subfamilies have structural and functional similarities, which presents a significant difficulty in screening and discovering of TRPCs modulators. In the past few years, only a limited number of selective modulators of TRPCs were detected; thus, additional research on more potent and more selective TRPCs modulators is needed. The present review focuses on the striking desired therapeutic effects of TRPCs modulators, which provides intel on the structural modification of TRPCs modulators and further pharmacological research. Importantly, TRPCs modulators can significantly facilitate future studies of TRPCs and TRPCs related diseases.