Galangin, a dietary flavonoid, ameliorates hyperglycaemia and lipid abnormalities in rats with streptozotocin-induced hyperglycaemia

THF induces apoptosis by downregulating initiation, promotion, and progression phase biomarkers in skin and lung carcinoma

3,5,7-Trihydroxy-2-phenylchromen-4-one (THF) possesses a diverse range of pharmacological activities. Evidence suggests that THF exerts anticancer activity by distinct mechanisms of action. This study explores the anticancer potential of THF in human lung (A549) and skin (A431) cancer cells by employing different antiproliferative assays. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, neutral red uptake, sulphorhodamine B, and cell motility assays were used to confirm the anticancer potential of THF. Cell target-based and quantitative reverse transcription polymerase chain reaction (qRT-PCR) assays were used to explore the effect of THF on the initiation, promotion and progression phase biomarkers of carcinogenesis. THF suppresses the activity of lipoxygenase-5 up to ~40% in both A549 and A431 cells and up to ~50% hyaluronidase activity in A549 cells. qRT-PCR assay reveals that THF inhibits the activity of phosphatidyl inositol-3 kinase/protein kinase B/mammalian target of rapamycin in both cell lines, which is responsible for the initiation of cancer. It also arrests the G2/M phase of the cell cycle in A431 cells and increases the sub-diploid population in both A549 and A431 cell lines which leads to cell death. Annexin V-FITC assay confirmed that THF induces apoptosis and necrosis in A431 and A549 cell lines. Further investigation revealed that THF not only enhances reactive oxygen species production but also modulates mitochondrial membrane potential in both cell lines. It significantly inhibits S-180 tumour formation at 5 and 10 mg/kg bw, i.p. dose. An acute skin toxicity study on mice showed that erythema and edema scores are within the acceptable range, besides acceptable drug-likeness properties and non-toxic effects on human erythrocytes. Conclusively, THF showed potent anticancer activity on skin and lung carcinoma cell lines, suppressed the level of the biomarkers and inhibited tumour growth in mice.

Bioprotective Role of Phytocompounds Against the Pathogenesis of Non-alcoholic Fatty Liver Disease to Non-alcoholic Steatohepatitis: Unravelling Underlying Molecular Mechanisms

Non-alcoholic fatty liver disease (NAFLD), with a global prevalence of 25%, continues to escalate, creating noteworthy concerns towards the global health burden. NAFLD causes triglycerides and free fatty acids to build up in the liver. The excessive fat build-up causes inflammation and damages the healthy hepatocytes, leading to non-alcoholic steatohepatitis (NASH). Dietary habits, obesity, insulin resistance, type 2 diabetes, and dyslipidemia influence NAFLD progression. The disease burden is complicated due to the paucity of therapeutic interventions. Obeticholic acid is the only approved therapeutic agent for NAFLD. With more scientific enterprise being directed towards the understanding of the underlying mechanisms of NAFLD, novel targets like lipid synthase, farnesoid X receptor signalling, peroxisome proliferator-activated receptors associated with inflammatory signalling, and hepatocellular injury have played a crucial role in the progression of NAFLD to NASH. Phytocompounds have shown promising results in modulating hepatic lipid metabolism and de novo lipogenesis, suggesting their possible role in managing NAFLD. This review discusses the ameliorative role of different classes of phytochemicals with molecular mechanisms in different cell lines and established animal models. These compounds may lead to the development of novel therapeutic strategies for NAFLD progression to NASH. This review also deliberates on phytomolecules undergoing clinical trials for effective management of NAFLD.

Nanophytomedicine: A promising practical approach in phytotherapy

The long and rich history of herbal therapeutic nutrients is fascinating. It is incredible to think about how ancient civilizations used plants and herbs to treat various ailments and diseases. One group of bioactive phytochemicals that has gained significant attention recently is dietary polyphenols. These compounds are commonly found in a variety of fruits, vegetables, spices, nuts, drinks, legumes, and grains. Despite their incredible therapeutic properties, one challenge with polyphenols is their poor water solubility, stability, and bioavailability. This means that they are not easily absorbed by the body when consumed in essential diets. Because of structural complexity, polyphenols with high molecular weight cannot be absorbed in the small intestine and after arriving in the colon, they are metabolized by gut microbiota. However, researchers are constantly working on finding solutions to enhance the bioavailability and absorption of these compounds. This study aims to address this issue by applying nanotechnology approaches to overcome the challenges of the therapeutic application of dietary polyphenols. This combination of nanotechnology and phytochemicals could cause a completely new field called nanophytomedicine or herbal nanomedicine.

Flavonoids: A treasure house of prospective pharmacological potentials

Flavonoids are organic compounds characterized by a range of phenolic structures, which are abundantly present in various natural sources such as fruits, vegetables, cereals, bark, roots, stems, flowers, tea, and wine. The health advantages of these natural substances are renowned, and initiatives are being taken to extract the flavonoids. Apigenin, galangin, hesperetin, kaempferol, myricetin, naringenin, and quercetin are the seven most common compounds belonging to this class. A thorough analysis of bibliographic records from reliable sources including Google Scholar, Web of Science, PubMed, ScienceDirect, MEDLINE, and others was done to learn more about the biological activities of these flavonoids. These flavonoids appear to have promising anti-diabetic, anti-inflammatory, antibacterial, antioxidant, antiviral, cytotoxic, and lipid-lowering activities, according to evidence from in vitro, in vivo, and clinical research. The review contains recent trends, therapeutical interventions, and futuristic aspects of flavonoids to treat several diseases like diabetes, inflammation, bacterial and viral infections, cancers, and cardiovascular diseases. However, this manuscript should be handy in future drug discovery. Despite these encouraging findings, a notable gap exists in clinical research, hindering a comprehensive understanding of the effects of flavonoids at both high and low concentrations on human health. Future investigations should prioritize exploring bioavailability, given the potential for high inter-individual variation. As a starting point for further study on these flavonoids, this review paper may promote identifying and creating innovative therapeutic uses.

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.

Potential Benefits of Antioxidant Phytochemicals in Type 2 Diabetes

The clinical relationship between diabetes and inflammation is well established. Evidence clearly indicates that disrupting oxidant-antioxidant equilibrium and elevated lipid peroxidation could be a potential mechanism for chronic kidney disease associated with type 2 diabetes mellitus (T2DM). Under diabetic conditions, hyperglycemia, especially inflammation, and increased reactive oxygen species generation are bidirectionally associated. Inflammation, oxidative stress, and tissue damage are believed to play a role in the development of diabetes. Although the exact mechanism underlying oxidative stress and its impact on diabetes progression remains uncertain, the hyperglycemia-inflammation-oxidative stress interaction clearly plays a significant role in the onset and progression of vascular disease, kidney disease, hepatic injury, and pancreas damage and, therefore, holds promise as a therapeutic target. Evidence strongly indicates that the use of multiple antidiabetic medications fails to achieve the normal range for glycated hemoglobin targets, signifying treatment-resistant diabetes. Antioxidants with polyphenols are considered useful as adjuvant therapy for their potential anti-inflammatory effect and antioxidant activity. We aimed to analyze the current major points reported in preclinical, in vivo, and clinical studies of antioxidants in the prevention or treatment of inflammation in T2DM. Then, we will share our speculative vision for future diabetes clinical trials.

Biochemical Changes Induced by the Administration of Cannabis sativa Seeds in Diabetic Wistar Rats

The present pilot study investigates the blood biochemical changes induced by hemp seeds in rats with diabetes. The composition of industrial hemp seeds, antioxidant activity, identification and quantification of phenols and fatty acids from hemp oil were determined. The Wistar adult rats used in the experiment were divided into three groups (n = 6) and kept under standard conditions. Group one, the control group (individuals without diabetes), and group two (diabetic individuals) received water and normal food ad libitum, while the third group, also including diabetic individuals, received specific food (hemp seeds) and water ad libitum. Subsequent blood biochemical parameters were determined. Hemp seeds had higher phenol (14 compounds), flavonoids and PUFA contents compared to other plants seeds. In addition, the antioxidant activity in Cannabis sativa was also increased. Moreover, the ratio between n-6 and n-3 was 4.41, ideal for different diseases. Additionally, all biochemical parameters showed significant changes following the treatment. It was shown that high doses of hemp seeds decreased diabetes-induced biochemical damage in rats most probably due to the high content of active compounds. In order to use these seeds in humans, it is essential to find out which hemp compounds are particularly responsible for these effects. Moreover, for the objective investigation of their effects, longer-term studies are needed.

Mitigation effect of galangin against aortic dysfunction and hypertrophy in rats with metabolic syndrome

Vascular alterations induced by a high-fat diet (HFD) are involved in the development of hypertension. Galangin, a flavonoid, is the major active compound isolated from galangal and propolis. The objective of this study was to investigate the effect of galangin on aortic endothelial dysfunction and hypertrophy, and the mechanisms involved in HFD-induced metabolic syndrome (MS) in rats. Male Sprague-Dawley rats (220-240 g) were separated into three groups: control + vehicle, MS + vehicle, and MS + galangin (50 mg/kg). Rats with MS received HFD plus 15% fructose solution for 16 weeks. Galangin or vehicle was orally administered daily for the final four weeks. Galangin reduced body weight and mean arterial pressure in HFD rats (p < 0.05). It also reduced circulating fasting blood glucose, insulin, and total cholesterol levels (p < 0.05). Impaired vascular responses to the exogenous acetylcholine observed in the aortic ring of HFD rats were restored by galangin (p < 0.05). However, the response to sodium nitroprusside did not differ between the groups. Galangin enhanced the expression of the aortic endothelial nitric oxide synthase (eNOS) protein and increased circulating nitric oxide (NO) levels in the MS group (p < 0.05). Aortic hypertrophy in HFD rats was alleviated by galangin (p < 0.05). Increases in tumour necrosis factor-alpha (TNF-α), interleukin (IL)-6 levels, angiotensin-converting enzyme activity and angiotensin II (Ang II) concentrations in rats with MS were suppressed in galangin treated group (p < 0.05). Furthermore, galangin reduced the upregulation of angiotensin II type I receptor (AT1R) and transforming growth factor-beta (TGF-β) expression in rats with MS (p < 0.05). In conclusion, galangin alleviates metabolic disorders and improves aortic endothelial dysfunction and hypertrophy in the MS group. These effects were consistent with increased NO availability, reduced inflammation, and suppressing Ang II/AT1R/TGF-β signalling pathway.

Investigation of the Potential Mechanism of Alpinia officinarum Hance in Improving Type 2 Diabetes Mellitus Based on Network Pharmacology and Molecular Docking

Objective

We used network pharmacology, molecular docking, and cellular analysis to explore the pharmacodynamic components and action mechanism of Alpinia officinarum Hance (A. officinarum) in improving type 2 diabetes mellitus (T2DM).

Methods

The protein-protein interaction (PPI) network, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed to predict the potential targets and mechanism of A. officinarum toward improving T2DM. The first 9 core targets and potential active compounds were docked using Discovery Studio 2019. Finally, IR-HepG2 cells and qPCR were applied to determine the mRNA expression of the top 6 core targets of the PPI network.

Results

A total of 29 active ingredients and 607 targets of A. officinarum were obtained. T2DM-related targets overlapped with 176 targets. The core targets of the PPI network were identified as AKT serine/threonine kinase 1 (AKT1), an activator of transcription 3 (STAT3), tumor necrosis factor (TNF), tumor protein p53 (TP53), SRC proto-oncogene, nonreceptor tyrosine kinase (SRC), epidermal growth factor receptor (EGFR), albumin (ALB), mitogen-activated protein kinase 1 (MAPK1), and peroxisome proliferator-activated receptor gamma (PPARG). A. officinarum performs an antidiabetic role via the AGE-RAGE signaling pathway, the HIF-1 signaling pathway, the PI3K-AKT signaling pathway, and others, according to GO and KEGG enrichment analyses. Molecular docking revealed that the binding ability of diarylheptanoid active components in A. officinarum to core target protein was higher than that of flavonoids. The cell experiments confirmed that the A. officinarum extracts improved the glucose uptake of IR-HepG2 cells and AKT expression while inhibiting the STAT3, TNF, TP53, SRC, and EGFR mRNA expression.

Conclusion

A. officinarum Hance improves T2DM by acting on numerous components, multiple targets, and several pathways. Our results lay the groundwork for the subsequent research and broaden the clinical application of A. officinarum Hance.

A Comprehensive Review on Anti-Inflammatory Response of Flavonoids in Experimentally-Induced Epileptic Seizures

Flavonoids, a group of natural compounds with phenolic structure, are becoming popular as alternative medicines obtained from plants. These compounds are reported to have various pharmacological properties, including attenuation of inflammatory responses in multiple health issues. Epilepsy is a disorder of the central nervous system implicated with the activation of the inflammatory cascade in the brain. The aim of the present study was to summarize the role of various neuroinflammatory mediators in the onset and progression of epilepsy, and, thereafter, to discuss the flavonoids and their classes, including their biological properties. Further, we highlighted the modulation of anti-inflammatory responses achieved by these substances in different forms of epilepsy, as evident from preclinical studies executed on multiple epilepsy models. Overall, the review summarizes the available evidence of the anti-inflammatory potential of various flavonoids in epilepsy.

Effect of quercetin and Abelmoschus esculentus (L.) Moench on lipids metabolism and blood glucose through AMPK-α in diabetic rats (HFD/STZ)

Phosphoenolpyruvate carboxykinase (PEPCK) is a key enzyme in the glyconeogenesis pathway. The AMP-activated protein kinase alpha (AMPK-α) pathway regulates PEPCK, which itself is activated by the AMP/ATP ratio and liver kinase B1 (KB1). The Abelmoschus esculentus (L.) Moench (okra) plant contains a large amount of quercetin that can function as an agonist or an antagonist. The aim of this study was to examine the effects of quercetin flavonoid and A. esculentus extract on the level of AMPK-α expression and associated metabolic pathways. The findings demonstrate that metformin, quercetin, and okra extract may significantly raise AMPK-α levels while significantly lowering PEPCK and hormone-sensitive lipase (HSL) levels, in addition to improving glucose and lipid profiles. By stimulating KB1, these substances increased AMPK-α activation. Additionally, AMPK-α activation improved insulin resistance and Glucose transporter type 4 (GLUT4) gene expression levels. Since AMPK-α maintains energy balance and its activity has not been reported to be inhibited so far, it could be a potent therapeutic target. PRACTICAL APPLICATIONS: The development of effective AMPK-α agonists and antagonists holds promise for the treatment of metabolic disorders like diabetes. Dietary polyphenols are a valuable source for developing new drugs. However, due to the lack of understanding of the underlying mechanisms of their effect on cells, their use in the treatment of diabetes is controversial. In addition to chemicals that have medicinal benefits, chemists are searching for less harmful substances. Using plants containing bioactive chemicals for this purpose can be a good alternative to chemical drugs.

Metabolic footprints of chitosan primed red kidney bean under restricted irrigation

Climate change has led to long term shift in temperature and weather regimes leading to unprecedented drought conditions. In this study varying degree of drought stress was imposed by restricting irrigation in red kidney bean along with application of chitosan as seed and foliar prime. LC-MS/MS was used to study the metabolic footprints (flavonoids and anthocyanin) in the red kidney bean varieties (BR 104 and VL Rajma 63). Presence of 14 flavonoid compounds and four anthocyanins (delphinidin>cyaniding>pelargonidin>malvidin) obtained from 0.25% chitosan primed red kidney bean were resolved through LC-MS/MS analysis. The concentration of flavonoid compounds in all the treatments was found in the order of naringenin>quercetin>luteolin>hesperetin>myricetin. Correlation studies revealed strong correlation of 0.95 among catechin-naringenin, galangin-hesperetin and epicatechin-kaempferol in BR 104 variety. Antioxidant activities were investigated by assessing radical scavenging activity, chelating power and reducing power assay in both varieties. Principle component (PC) analysis depicted through biplot was showed 44.7% contribution was found towards PC1 and 28.6% towards PC2 in BR 104 variety. 0.25% chitosan as seed and foliar priming with imposed drought stress was found to improve the antioxidant contents of seed by regulating polyphenols which have diverse role in stress management.

Omarigliptin/galangin combination mitigates lipopolysaccharide-induced neuroinflammation in rats: Involvement of glucagon-like peptide-1, toll-like receptor-4, apoptosis and Akt/GSK-3β signaling

AIMS

The objectives of this work were to assess the possibility of administration of omarigliptin and/or galangin to combat lipopolysaccharide (LPS)-induced neuroinflammation in rats and to explore the possible mechanisms that might contribute to their actions.

MATERIALS AND METHODS

In a rat model of LPS-induced neuroinflammation, the changes in the behavioral tests, biochemical parameters, and the histopathological picture were assessed.

KEY FINDINGS

Administration of either omarigliptin or galangin to LPS-injected rats was able to significantly improve the behavioral changes with restoration of the oxidant/antioxidant balance, decrement of toll-like receptor-4 levels, and amelioration of the neuroinflammation associated with inhibition of apoptosis and restoration of glucagon-like peptide-1 levels in the cerebral tissues. In addition, omarigliptin and/or galangin significantly reduced the levels of phospho-Akt and glycogen synthase kinase 3 beta (GSK-3β) and significantly increased the expression of beclin-1 in the cerebral tissues compared versus the group treated with LPS alone. As a result, these changes were positively reflected on the histopathological and the electron microscopic picture of the cerebral tissues. These beneficial effects were maximally evidenced in rats treated with omarigliptin/galangin combination relative to the use of either omarigliptin or galangin alone.

SIGNIFICANCE

Omarigliptin/galangin combination might be proposed as a promising therapeutic line for mitigation of the pathophysiologic events of LPS-induced neuroinflammation.

Cardioprotective effects of phytopigments via multiple signaling pathways

BACKGROUND

Cardiovascular diseases (CVDs) are among the deadliest non-communicable diseases, and millions of dollars are spent every year to combat CVDs. Unfortunately, the multifactorial etiology of CVDs complicates the development of efficient therapeutics. Interestingly, phytopigments show significant pleiotropic cardioprotective effects both in vitro and in vivo.

PURPOSE

This review gives an overview of the cardioprotective effects of phytopigments based on in vitro and in vivo studies as well as clinical trials.

METHODS

A literature-based survey was performed to collect the available data on cardioprotective activities of phytopigments via electronic search engines such as PubMed, Google Scholar, and Scopus.

RESULTS

Different classes of phytopigments such as carotenoids, xanthophylls, flavonoids, anthocyanins, anthraquinones alleviate major CVDs (e.g., cardiac hypertrophy, atherosclerosis, hypertension, cardiotoxicities) via acting on signaling pathways related to AMPK, NF-κB, NRF2, PPARs, AKT, TLRs, MAPK, JAK/STAT, NLRP3, TNF-α, and RA.

CONCLUSION

Phytopigments represent promising candidates to develop novel and effective CVD therapeutics. More randomized, placebo-controlled clinical studies are recommended to establish the clinical efficacy of phytopigments.

Targeting PI3K/Akt/mTOR Pathway by Different Flavonoids: A Cancer Chemopreventive Approach

Cancer is, globally, one of the main causes of death. Even though various therapies are available, they are still painful because of their adverse side effects. Available treatments frequently fail due to unpromising responses, resistance to classical anticancer drugs, radiation therapy, chemotherapy, and low accessibility to tumor tissues. Developing novel strategies to minimize adverse side effects, improve chemotherapy sensitivity, and control cancer progression is needed. Many studies have suggested small dietary molecules as complementary treatments for cancer patients. Different components of herbal/edible plants, known as flavonoids, have recently garnered attention due to their broad biological properties (e.g., antioxidant, antiviral, antimicrobial, anti-inflammatory, anti-mutagenic, anticancer, hepatoprotective, and cardioprotective). These flavonoids have shown anticancer activity by affecting different signaling cascades. This article summarizes the key progress made in this area and discusses the role of flavonoids by specifically inhibiting the PI3K/Akt/mTOR pathway in various cancers.

Polyphenols as anticancer agents: Toxicological concern to healthy cells

Polyphenols are a group of diverse chemical compounds present in a wide range of plants. Various biological properties such as antiallergic, antiviral, antibacterial, anticarcinogenic, antiinflammatory, antithrombotic, vasodilatory, and hepatoprotective effect of different polyphenols have been reported in the scientific literature. The major classes of polyphenols are flavonoids, stilbenoids, lignans, and polyphenolic acids. Flavonoids are a large class of food constituents comprising flavones, isoflavanones, flavanones, flavonols, catechins, and anthocyanins sub-classes. Even with seemingly broad biological activities, their use is minimal clinically. Among the other concurrent problems such as limited bioavailability, rapid metabolism, untargeted delivery, the toxicity associated with these polyphenols has been a topic of concern lately. These polyphenols have been reported to result in different forms of toxicity that include organ toxicity, genotoxicity, mutagenicity, cytotoxicity, etc. In the present article, we have tried to unravel the toxicological aspect of these polyphenols to healthy cells. Further high-quality studies are needed to establish the clinical efficacy and toxicology concern leading to further exploration of these polyphenols.

Galangin Attenuates Liver Injury, Oxidative Stress and Inflammation, and Upregulates Nrf2/HO-1 Signaling in Streptozotocin-Induced Diabetic Rats

Chronic hyperglycemia increases the risk of liver damage. Oxidative stress and aberrant inflammatory response are entangled in diabetes-associated liver injury. This study evaluated the protective effect of the flavonoid galangin (Gal) on glucose intolerance, liver injury, oxidative stress, inflammatory response, and Nrf2/HO-1 signaling in diabetic rats. Diabetes was induced by streptozotocin (STZ), and the rats received Gal for six weeks. STZ-induced rats showed glucose intolerance, hypoinsulinemia, elevated glycated hemoglobin (HbA1c), and decreased liver glycogen. Gal ameliorated glucose intolerance, reduced HbA1c%, increased serum insulin and liver glycogen and hexokinase activity, and suppressed glycogen phosphorylase, glucose-6-phosphatase and fructose-1,6-biphosphatase in diabetic rats. Circulating transaminases, ALP and LDH, and liver ROS, MDA, TNF-α, IL-1β, and IL-6 were increased and GSH, SOD, and CAT were diminished in diabetic rats. In addition, diabetic rats exhibited multiple histopathological alterations and marked collagen deposition. Treatment with Gal mitigated liver injury, prevented histopathological alterations, decreased ROS, MDA, pro-inflammatory cytokines, Bax and caspase-3, and enhanced cellular antioxidants and Bcl-2. Gal downregulated hepatic Keap1 in diabetic rats and upregulated Nrf2 and HO-1 mRNA as well as HO-1 activity. Molecular modeling studies revealed the ability of Gal to bind to and inhibit NF-κB and Keap1, and also showed its binding pattern with HO-1. In conclusion, Gal ameliorates hyperglycemia, glucose intolerance, oxidative stress, inflammation, and apoptosis in diabetic rats. Gal improved carbohydrate metabolizing enzymes and upregulated Nrf2/HO-1 signaling.

Flavonoids as Human Intestinal α-Glucosidase Inhibitors

Certain flavonoids can influence glucose metabolism by inhibiting enzymes involved in carbohydrate digestion and suppressing intestinal glucose absorption. In this study, four structurally-related flavonols (quercetin, kaempferol, quercetagetin and galangin) were evaluated individually for their ability to inhibit human α-glucosidases (sucrase, maltase and isomaltase), and were compared with the antidiabetic drug acarbose and the flavan-3-ol(−)-epigallocatechin-3-gallate (EGCG). Cell-free extracts from human intestinal Caco-2/TC7 cells were used as the enzyme source and products were quantified chromatographically with high accuracy, precision and sensitivity. Acarbose inhibited sucrase, maltase and isomaltase with IC₅₀ values of 1.65, 13.9 and 39.1 µM, respectively. A similar inhibition pattern, but with comparatively higher values, was observed with EGCG. Of the flavonols, quercetagetin was the strongest inhibitor of α-glucosidases, with inhibition constants approaching those of acarbose, followed by galangin and kaempferol, while the weakest were quercetin and EGCG. The varied inhibitory effects of flavonols against human α-glucosidases depend on their structures, the enzyme source and substrates employed. The flavonols were more effective than EGCG, but less so than acarbose, and so may be useful in regulating sugar digestion and postprandial glycaemia without the side effects associated with acarbose treatment.

The Effect of Galangin on the Regulation of Vascular Contractility via the Holoenzyme Reactivation Suppressing ROCK/CPI-17 rather than PKC/CPI-17

In this study, we investigated the influence of galangin on vascular contractibility and to determine the mechanism underlying the relaxation. Isometric contractions of denuded aortic muscles were recorded and combined with western blot analysis which was performed to measure the phosphorylation of phosphorylation-dependent inhibitory protein of myosin phosphatase (CPI-17) and myosin phosphatase targeting subunit 1 (MYPT1) and to evaluate the effect of galangin on the RhoA/ROCK/CPI-17 pathway. Galangin significantly inhibited phorbol ester-, fluoride- and thromboxane mimetic-induced vasoconstrictions regardless of endothelial nitric oxide synthesis, suggesting its direct effect on vascular smooth muscle. Galangin significantly inhibited the fluoridedependent increase in pMYPT1 and pCPI-17 levels and phorbol 12,13-dibutyrate-dependent increase in pERK1/2 level, suggesting repression of ROCK and MEK activity and subsequent phosphorylation of MYPT1, CPI-17 and ERK1/2. Taken together, these results suggest that galangin-induced relaxation involves myosin phosphatase reactivation and calcium desensitization, which appears to be mediated by CPI-17 dephosphorylation via not PKC but ROCK inactivation.

Effect of Alpinia officinarum extract on reproductive damages in streptozotocin induced diabetic male rats

PURPOSE

Infertility is one of the systemic problems in diabetic men. The purpose of the present study is investigation of the effects of the Alpinia officinarum (AO) hydro-alcoholic extract on the reproductive system damages in diabetic male rats.

METHODS

Twenty four male rats were randomly assigned into 4 groups (n = 6); i.e., control, diabetic control, and diabetic rats treated orally with AO extract (200 and 500 mg kg-1). A single dose (60 mg kg-1) of streptozotocin (STZ) was injected intraperitoneally (IP) to induce diabetes. After 8 weeks of treatment, blood samples, testis, and cauda epididymis were excised to evaluate specific hormonal changes, sperm parameters, and testis morphology.

RESULTS

Diabetic control rats showed remarkably lower body and testicular weights, testicular volumes, and sperm parameters compared with the control group (p <0.05). Diabetic control rats also exhibited significantly decreased serum testosterone and follicle stimulating hormone (FSH). Sperm parameters were considerably enhanced in diabetic animals gavaged with AO extract. Testosterone levels were significantly elevated by administrating 500 mg kg-1 AO extract to the diabetic control rats (p <0.05). The morphological assessment of testis of treatment group (500 mg kg-1) indicated remarkable differences (p <0.05) by increasing the seminiferous tubules diameter (STD) and thickness of the seminiferous epithelium (TSE) compared with diabetic control rats.

CONCLUSION

As demonstrated by the results, AO extract ameliorated sperm damage and improved sperm morphology besides improving histological damage in the testis in diabetic rats. In addition, the dose of 500 mg kg-1 worked more efficiently than 200 mg kg-1.

Kuanxiong Aerosol () in Treatment of Angina Pectoris: A Literature Review and Network Pharmacology

Angina pectoris (AP) is the most common symptom of cardiovascular diseases, which seriously affects the quality of life in cardiovascular patients. Kuanxiong (KX) Aerosol (), a compound preparation that consists of 5 traditional Chinese medicines: Herba Asari , Rhizoma Alpiniae Officinarum, Lignum Santali Albi, Fructus Piperis Longi, and Borneolum, has been used in the treatment of AP for many years, exhibiting a significant curative effect and less side-effect. For the convenience and comprehensive understanding of KX Aerosol, this review systematically summarizes evidence on KX Aerosol in the treatment of AP including the pharmacological effects of its composition, clinical research, animal experiments, and network pharmacology prediction. Meanwhile, we highlight the research limitation of KX Aerosol at present. This review may guide the clinical application of KX Aerosol and further provide a reference for the research of AP.

Galangin attenuates oxidative stress-mediated apoptosis in high glucose-induced renal tubular epithelial cells through modulating renin-angiotensin system and PI3K/AKT/mTOR pathway

This study was to evaluate the regulatory network among Galangin (Gal), oxidative stress, and renin-angiotensin system (RAS) in diabetic nephropathy (DN) in vitro. A cell model of DN was set up by exposing HK-2 cells to high glucose (HG, 30 mM) for 48 h and Gal was applied at 10 μM when needed. mRNA expression was analyzed by qPCR and protein level was detected by western blot. Malondialdehyde level and superoxide dismutase activity were evaluated by commercial kits. We analyzed cell viability by CCK8 assay and apoptosis by flow cytometry. DCFH-DA staining was conveyed for reactive oxygen species detection. HG induced RAS activation, oxidative stress, while inhibited cell viability. Gal suppressed oxidative stress-mediated apoptosis of HK-2 cells under the stimulation of HG via inhibiting RAS activation. Moreover, overexpression of AT1R, a RAS gene, could restrain the mitigative effect of Gal on cell injury. Furthermore, repression of RAS induced by AT1R knockdown partially reversed HG-induced PI3K/AKT/mTOR activation and oxidative stress in HK-2 cells. Also, AKT activation could antagonize Gal's functional roles in renal cell damage. Collectively, Gal alleviates HG-induced oxidative stress injury of renal tubular epithelial cells through PI3K/AKT/mTOR signal via modulating RAS activation. This finding would help to better understand mechanism of DN development and support future studies.

Galangin Resolves Cardiometabolic Disorders through Modulation of AdipoR1, COX-2, and NF-κB Expression in Rats Fed a High-Fat Diet

Galangin is a natural flavonoid. In this study, we evaluated whether galangin could alleviate signs of metabolic syndrome (MS) and cardiac abnormalities in rats receiving a high-fat (HF) diet. Male Sprague–Dawley rats were given an HF diet plus 15% fructose for four months, and they were fed with galangin (25 or 50 mg/kg), metformin (100 mg/kg), or a vehicle for the last four weeks. The MS rats exhibited signs of MS, hypertrophy of adipocytes, impaired liver function, and cardiac dysfunction and remodeling. These abnormalities were alleviated by galangin (p < 0.05). Interleukin-6 and tumor necrosis factor-α concentrations and expression were high in the plasma and cardiac tissue in the MS rats, and these markers were suppressed by galangin (p < 0.05). These treatments also alleviated the low levels of adiponectin and oxidative stress induced by an HF diet in rats. The downregulation of adiponectin receptor 1 (AdipoR1) and cyclooxygenase-2 (COX-2) and the upregulation of nuclear factor kappa B (NF-κB) expression were recovered in the galangin-treated groups. Metformin produced similar effects to galangin. In conclusion, galangin reduced cardiometabolic disorders in MS rats. These effects might be linked to the suppression of inflammation and oxidative stress and the restoration of AdipoR1, COX-2, and NF-κB expression.

Galangin Alleviates Tumor Progression and Metastasis in Intraperitoneal Ovarian Cancer Model via Inhibiting Janus Kinase 1/Signal Transduction and Activator of Transcription 3 Signaling

To investigate the impact of galangin on tumor progression and metastasis in intraperitoneal ovarian cancer model. Ovarian cancer cells were treated with DMSO or galectin, cell viability was detected by MTS or acid phosphatase assay, SKOV3 cells were transfected with STAT3 targeted shRNA and the expression of signal transduction-related proteins in cells was analyzed by immunoblotting assay, the expression of IL-6, IL-2, INF-y was estimated by enzyme-linked immunosorbent assay the peritoneal metastasis model of ovarian cancer was established using shSTAT3 transfected or untransfected SKOV3 cells and treated with galangin or DMSO. Tumor mass, number of small tumor nodules and ascites volume were detected in the mouse model. Ovarian cancer-bearing mice treated with galangin showed a dramatic decreased tumor burden as demonstrated by the 25 times-reduced total weight of small tumor nodules, 60%-reduced primary tumors, attenuated luciferase activity and completely blocked ascites production. Moreover, galangin inhibited cell viability in vitro in a concentration-dependent manner. Further, p-STAT3 was suppressed by galangin treatment both in vivo and vitro. Galangin inhibited the expression of p-JAK1, the upstream signaling of p-STAT3 and IL-6 in the downstream. Meanwhile, knockdown of STAT3 by shSTAT3 transfection mimicked the therapeutic effects of galangin in vivo and vitro. Galangin supresses IL-6 secretion, peritoneal metastasis and ascites production by inhibiting JAK1/STAT3 signaling.

Potential Role of Propolis in the Prevention and Treatment of Metabolic Diseases

Propolis is a resinous mixture with a complex chemical composition, produced by honeybees and stingless bees from a variety of vegetal sources. In the last decades, propolis was extensively researched, multiple studies confirming its anti-inflammatory, antioxidant, antimicrobial, and wound-healing properties. More recently, due to an exponential increase in the number of patients with metabolic diseases, there is also a growing interest in the study of antidiabetic, antihyperlipidemic, and anti-obesity effects of propolis. The aim of this review was to evaluate the potential role of propolis in the prevention and treatment of metabolic diseases like diabetes mellitus, dyslipidemia, and obesity. The preclinical in vivo and in vitro pharmacological models investigating antidiabetic, antihyperlipidemic, and anti-obesity effects of propolis were reviewed with a focus on the putative mechanisms of actions of several chemical constituents. Additionally, the available clinical studies and an evaluation of the safety profile of propolis were also presented.

Galangin attenuates diabetic cardiomyopathy through modulating oxidative stress, inflammation and apoptosis in rats

Cardiovascular complications are the leading cause of morbidity in diabetes. Oxidative stress and inflammation are implicated in the development and progression of diabetic cardiomyopathy (DCM). This study explored the cardioprotective effect of galangin (Gal), a natural flavonoid with radical-scavenging and anti-inflammatory activities, in diabetic rats. An experimental diabetic rat model was achieved by a single injection of 50 mg/kg streptozotocin. Gal (15 mg/kg) was administered daily for six weeks and the samples were then collected. Diabetic rats exhibited hyperglycemia, increased glycosylated hemoglobin, triglycerides and cholesterol levels and reduced serum insulin. Serum troponin I, CK-MB and LDH were increased in diabetic rats. Furthermore, hearts of diabetic rats were characterized by elevated malondialdehyde, protein carbonyl, NF-κB p65, TNF-α, IL-1β, iNOS, IL-6, Bax, caspase-3 and 8-Oxo-dG, and decreased superoxide dismutase, catalase, reduced GSH, and Bcl-2. Gal ameliorated hyperglycemia, dyslipidemia, and heart function markers, and prevented histopathological alterations in diabetic rats. In addition, Gal attenuated cardiac oxidative injury, inflammation and apoptosis, and boosted antioxidant defenses. In conclusion, Gal has a protective effect on cardiomyopathy by attenuating hyperglycemia, dyslipidemia, oxidative stress and inflammation in diabetic rats.

Camel milk as an alternative treatment regimen for diabetes therapy

Camel milk is a valuable source of nutrition with a wide range of therapeutic effects. Its unique composition helps to regulate the blood glucose level. The current study is aimed to evaluate the antidiabetic and hepatoprotective effects, as well as lipid profile restoration of camel milk in the diabetic mouse model. This innovative study evaluates the therapeutic effects of camel milk in diabetic mice by simultaneous measurement of blood glucose, HbA1c, ALT, AST, TG, cholesterol, and histopathological studies. The results showed that camel milk has significantly reduced blood glucose, HbA1c (p < .001), aspartate transaminase (AST), alanine transaminase (ALT) (p < .01), triglyceride (TG), and cholesterol (p < .01), compared to that in the diabetic control group. Also, the therapeutic effects of camel milk were completely comparable with the antidiabetic drug glibenclamide. The results of this study suggest that camel milk could be used as a proper alternative treatment regimen for diabetes therapy.

Protective Role of Loranthus regularis against Liver Dysfunction, Inflammation, and Oxidative Stress in Streptozotocin Diabetic Rat Model

Earlier studies revealed the potential therapeutic values of Loranthus regularis (L. regularis). This study evaluated Loranthus regularis (L. regularis) extract systemic antidiabetic effects and benefits against diabetic hepatocellular injuries through antioxidant and anti-inflammatory pathways using the streptozotocin (STZ) model in Wistar albino rats. After diabetes induction, animals were orally treated with L. regularis extract for 4 weeks. Serum levels of glucose, insulin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol (TC), total triglycerides (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) were estimated. Furthermore, tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), interleukin-6 (IL-6), caspase-3, nitric oxide (NO), and prostaglandin E-2 (PGE-2) were estimated in serum. In liver, thiobarbituric acid reactive substances (TBARSs) and reduced glutathione (GSH) as well as the proinflammatory cytokines and enzymatic activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reeducates (GR), and glutathione-S-transferase (GST) were assayed. Finally, the degree of hepatic tissue damage was evaluated histologically. Treatment of the diabetic rats with L. regularis extract markedly reduced the elevated serum levels of glucose, ALT, AST, TC, TG, LDL, TNF-α, IL-1β, IL-6, caspase-3, NO, and PGE-2. L. regularis extract also improved serum levels of insulin and HDL. The elevated TBARS, TNF-α, IL-1β, and IL-6 levels in hepatic tissue of diabetic animals were reduced by L. regularis. Moreover, L. regularis extract significantly restored the diminished hepatic GSH level and enzymatic activities of SOD, CAT, GPx, GR, and GST in diabetic animals. The biochemical protective effects of L. regularis were associated with improved histological hepatocellular integrity and architecture. Taken together, L. regularis has therapeutic effects against diabetic-induced hepatic complications. The restored liver functions and cellular damage might be mediated through free radicals scavenging and proinflammatory cytokine inhibition.

The Coming Age of Flavonoids in the Treatment of Diabetic Complications

Diabetes mellitus (DM), and its micro and macrovascular complications, is one of the biggest challenges for world public health. Despite overall improvement in prevention, diagnosis and treatment, its incidence is expected to continue increasing over the next years. Nowadays, finding therapies to prevent or retard the progression of diabetic complications remains an unmet need due to the complexity of mechanisms involved, which include inflammation, oxidative stress and angiogenesis, among others. Flavonoids are natural antioxidant compounds that have been shown to possess anti-diabetic properties. Moreover, increasing scientific evidence has demonstrated their potential anti-inflammatory and anti-oxidant effects. Consequently, the use of these compounds as anti-diabetic drugs has generated growing interest, as is reflected in the numerous in vitro and in vivo studies related to this field. Therefore, the aim of this review is to assess the recent pre-clinical and clinical research about the potential effect of flavonoids in the amelioration of diabetic complications. In brief, we provide updated information concerning the discrepancy between the numerous experimental studies supporting the efficacy of flavonoids on diabetic complications and the lack of appropriate and well-designed clinical trials. Due to the well-described beneficial effects on different mechanisms involved in diabetic complications, the excellent tolerability and low cost, future randomized controlled studies with compounds that have adequate bioavailability should be evaluated as add-on therapy on well-established anti-diabetic drugs.

Aqueous extract from Mangifera indica Linn. (Anacardiaceae) leaves exerts long-term hypoglycemic effect, increases insulin sensitivity and plasma insulin levels on diabetic Wistar rats

BACKGROUND

Diabetes mellitus is one of the most common todays public health problems. According to a survey by the World Health Organization, this metabolic disorder has reached global epidemic proportions, with a worldwide prevalence of 8.5% in the adult population.

OBJECTIVES

The present study aimed to investigate the hypoglycemic effect of aqueous extract of Mangifera indica (EAMI) leaves in streptozotocin-induced diabetic rats.

METHODS

Sixty male rats were divided into 2 groups: Normoglycemic and Diabetic. Each group was subdivided into negative control, glibenclamide 3 or 10 mg/kg, EAMI 125, 250, 500, and 1000 mg/kg. Intraperitoneal injection of streptozotocin 100 mg/kg was used to DM induction. The hypoglycemic response was assessed acutely after two and four weeks of treatment. After a 6-hour fasting period, the fasting blood glucose of animals was verified, and 2.5 g/kg glucose solution was orally administered. The insulin tolerance test and plasma insulin levels assessment were performed in the morning after fasting of 12 to 14 hours.

RESULTS AND CONCLUSION

The chemical analysis of EAMI showed high levels of phenolic compounds. There was no significant difference in fasting blood glucose between normoglycemic and diabetic groups, and that EAMI did not have an acute effect on diabetes. After two and four weeks of treatment, the extract significantly reduced blood glucose levels, exceeding glibenclamide effects. EAMI was effective in maintaining the long-term hypoglycemic effect, as well as, significantly increased the sensitivity of diabetic animals to insulin and the plasma insulin level.

Galangin ameliorates cardiac remodeling via the MEK1/2-ERK1/2 and PI3K-AKT pathways

Cardiac remodeling is associated with inflammation and apoptosis. Galangin, as a natural flavonol, has the potent function of regulating inflammation and apoptosis, which are factors related to cardiac remodeling. Beginning 3 days after aortic banding (AB) or Sham surgery, mice were treated with galangin for 4 weeks. Cardiac remodeling was assessed according to echocardiographic parameters, histological analyses, and hypertrophy and fibrosis markers. Our results showed that galangin administration attenuated cardiac hypertrophy, dysfunction, and fibrosis response in AB mice and angiotensin II-treated H9c2 cells. The inhibitory action of galangin in cardiac remodeling was mediated by MEK1/2-extracellular-regulated protein kinases 1/2 (ERK1/2)-GATA4 and phosphoinositide 3-kinase (PI3K)-protein kinase B (AKT)-glycogen synthase kinase 3β (GSK3β) activation. Furthermore, we found that galangin inhibited inflammatory response and apoptosis. Our findings suggest that galangin protects against cardiac remodeling through decreasing inflammatory responses and apoptosis, which are associated with inhibition of the MEK1/2-ERK1/2-GATA4 and PI3K-AKT-GSK3β signals.

Discovery of Galangin as a Potential DPP-4 Inhibitor That Improves Insulin-Stimulated Skeletal Muscle Glucose Uptake: A Combinational Therapy for Diabetes

Dipeptidyl peptidase-4 (DPP-4) is a well-known therapeutic drug target proven to reduce blood glucose levels in diabetes mellitus, and clinically, DPP-4 inhibitors are used in combination with other anti-diabetic agents. However, side effects and skeletal muscle health are not considered in the treatment for diabetic patients. Recently, natural compounds have been proven to inhibit DPP-4 with fewer side effects. In this work, initially, molecular docking simulations revealed that a natural compound, Galangin, possess a binding energy of −24 KJ/mol and interaction residues SER 630 and TYR 547, that are responsible for potent DPP-4 inhibition. In vitro studies showed that galangin not only inhibits DPP-4 in a concentration-dependent manner but also regulates glucose levels, enabling the proliferation of rat L6 skeletal muscle cells. The combination of galangin with insulin benefits regulation of glucose levels significantly in comparison to galangin alone (p < 0.05). These findings suggest the beneficial effect of the use of galangin, both alone or in combination with insulin, to reduce glucose levels and improve skeletal muscle health in diabetes mellitus.