Hispidulin Exerts Anti-osteoporotic Activity in Ovariectomized Mice via Activating AMPK Signaling Pathway

Alpha-lipoic Acid Prevents Bone Loss in Type 2 Diabetes and Postmenopausal Osteoporosis Coexisting Conditions by Modulating the YAP/Glut4 Pathway

This study aims to characterize the bone-protecting effects of Alpha-lipoic acid (ALA), a potent antioxidant, against the detrimental effects of the coexistence of type 2 diabetes mellitus (T2DM) and postmenopausal osteoporosis (POP) and identify the possible mechanisms with particular reference to its modulation of YAP/Glut4 pathway. The T2DM and POP coexisting model was induced in mice by high fat diet (HFD) + Streptozocin (STZ) + ovariectomy (OVX). The mice in the treatment groups were given ALA for 10 weeks. In the in vitro study, MC3T3-E1 cells were induced with 500 μM methylglyoxal for 24 h with or without pretreatment with ALA for 24 h. The oxidative and antioxidative biomarkers, bone microarchitecture, histo-morphology, and related protein expression of apoptosis, osteogenic differentiation and the YAP/Glut4 pathway were detected. The results showed ALA could improve glucose tolerance, inhibit oxidative stress and apoptosis and alleviate bone loss. Further study by siRNA technology revealed that the YAP/Glut4 pathway was implicated in the pathogenesis of bone loss due to the coexistence of T2DM and POP. Taken together, the present study has demonstrated for the first time that ALA exerts potent protective effects against bone loss in T2DM and POP coexisting conditions by modulating the YAP/Glut4 pathway.

Hispidulin: a promising anticancer agent and mechanistic breakthrough for targeted cancer therapy

Cancer is a complex disease characterized by dysregulated cell growth and division, posing significant challenges for effective treatment. Hispidulin, a flavonoid compound, has shown promising biological effects, particularly in the field of anticancer research. The main objective of this study is to investigate the anticancer properties of hispidulin and gain insight into its mechanistic targets in cancer cells. A comprehensive literature review was conducted to collect data on the anticancer effects of hispidulin. In vitro and in vivo studies were analyzed to identify the molecular targets and underlying mechanisms through which hispidulin exerts its anticancer activities. Hispidulin has shown significant effects on various aspects of cancer, including cell growth, proliferation, cell cycle regulation, angiogenesis, metastasis, and apoptosis. It has been observed to target both extrinsic and intrinsic apoptotic pathways, regulate cell cycle arrest, and modulate cancer progression pathways. The existing literature highlights the potential of hispidulin as a potent anticancer agent. Hispidulin exhibits promising potential as a therapeutic agent for cancer treatment. Its ability to induce apoptosis and modulate key molecular targets involved in cancer progression makes it a valuable candidate for further investigation. Additional pharmacological studies are needed to fully understand the specific targets and signaling pathways influenced by hispidulin in different types of cancer. Further research will contribute to the successful translation of hispidulin into clinical settings, allowing its utilization in conventional and advanced cancer therapies with improved therapeutic outcomes and reduced side effects.

Hispidulin exerts a protective effect against oleic acid induced-ARDS in the rat via inhibition of ACE activity and MAPK pathway

This study investigates the protective role of Hispidulin on acute respiratory distress syndrome (ARDS) in rats. Rats were divided into three groups: control, ARDS, ARDS+ Hispidulin. The ARDS models were established by injecting rats with oleic acid. Hispidulin (100 mg/kg) was injected i.p. an hour before ARDS. Myeloperoxidase (MPO), Interleukin-8 (IL-8), Mitogen-activated protein kinases (MAPK), Lipid Peroxidation (LPO), Superoxide Dismutase (SOD), Glutathione (GSH), and Angiotensin-converting enzyme (ACE) were determined by ELISA. Tumor necrosis factor-alpha (TNF-α) expression was described by RT-qPCR. Caspase-3 immunostaining was performed to evaluate apoptosis. Compared with the model group, a significant decrease was observed in the MPO, IL-8, MAPK, ACE, LPO levels, and TNF-α expression in the ARDS+ Hispidulin group. Moreover, reduced caspase-3 immunoreactivity and activity of ACE were detected in the Hispidulin+ARDS group. The protective effect of Hispidulin treatment may act through inhibition of the ACE activity and then regulation of inflammatory cytokine level and alteration of apoptosis.

Hispidulin Inhibits the Vascular Inflammation Triggered by Porphyromonas gingivalis Lipopolysaccharide

Hispidulin is a natural bioactive flavonoid that has been studied for its potential therapeutic properties, including its anti-inflammatory, antioxidant, and neuroprotective effects. The aim of this study was to explore whether hispidulin could inhibit the endothelial inflammation triggered by Porphyromonas gingivalis (P. gingivalis) lipopolysaccharide (LPS). The adhesion of monocytes to the vascular endothelium was evaluated through in vitro and ex vivo monocyte adhesion assays. We analyzed the migration of monocytes across the endothelial layer using a transmigration assay. The results showed that treatment with hispidulin decreased the P. gingivalis LPS-induced adhesion of monocytes to endothelial cells and their migration by suppressing the P. gingivalis LPS-triggered expression of intercellular adhesion molecule-1 (ICAM-1) through downregulating nuclear factor-қB (NF-қB). In addition, hispidulin inhibited P. gingivalis LPS-induced mitogen-activated protein kinases (MAPKs) and AKT in endothelial cells. Altogether, the results indicate that hispidulin suppresses the vascular inflammation induced by P. gingivalis LPS. Mechanistically, it prevents the adhesion of monocytes to the vascular endothelium and migration and inhibits NF-қB, MAPKs, and AKT signaling in endothelial cells.

Advent of phytobiologics and nano-interventions for bone remodeling: a comprehensive review

Bone metabolism constitutes the intricate processes of matrix deposition, mineralization, and resorption. Any imbalance in these processes leads to traumatic bone injuries and serious disease conditions. Therefore, bone remodeling plays a crucial role during the regeneration process maintaining the balance between osteoblastogenesis and osteoclastogenesis. Currently, numerous phytobiologics are emerging as the new therapeutics for the treatment of bone-related complications overcoming the synthetic drug-based side effects. They can either target osteoblasts, osteoclasts, or both through different mechanistic pathways for maintaining the bone remodeling process. Although phytobiologics have been widely used since tradition for the treatment of bone fractures recently, the research is accentuated toward the development of osteogenic phytobioactives, constituent-based drug designing models, and efficacious delivery of the phytobioactives. To achieve this, different plant extracts and successful isolation of their phytoconstituents are critical for osteogenic research. Hence, this review emphasizes the phytobioactives based research specifically enlisting the plants and their constituents used so far as bone therapeutics, their respective isolation procedures, and nanotechnological interventions in bone research. Also, the review enlists the vast array of folklore plants and the newly emerging nano-delivery systems in treating bone injuries as the future scope of research in the phytomedicinal orthopedic applications.

Treat more than heat-New therapeutic implications of Cimicifuga racemosa through AMPK-dependent metabolic effects

BACKGROUND

Cimicifuga racemosa extracts (CRE) have obtained a "well-established use status" in the treatment of postmenopausal (i.e., climacteric) complaints, which predominantly include vasomotor symptoms such as hot flushes and sweating, as well as nervousness, irritability, and metabolic changes. Although characteristic postmenopausal complaints are known for a very long time and the beneficial effects of CRE on climacteric symptoms are well accepted, both the pathophysiology of postmenopausal symptoms and the mechanism of action of CREs are not yet fully understood. In particular, current hypotheses suggest that changes in the α-adrenergic and serotonergic signaling pathways secondary to estrogen depletion are responsible for the development of hot flushes.

PURPOSE

Some of the symptoms associated with menopause cannot be explained by these hypotheses. Therefore, we attempted to extend our classic understanding of menopause by integrating of partly age-related metabolic impairments.

METHODS

A comprehensive literature survey was performed using the PubMed database for articles published through September 2021. The following search terms were used: (cimicifuga OR AMPK) AND (hot flush* OR hot flash* OR menopaus* OR osteoporos* OR cancer OR antioxida* OR cardiovasc*). No limits were set with respect to language, and the references cited in the articles retrieved were used to identify additional publications.

RESULTS

We found that menopause is a manifestation of the general aging process, with specific metabolic changes that aggravate menopausal symptoms, which are accelerated by estrogen depletion and associated neurotransmitter dysregulation. Cimicifuga extracts with their metabolic effects mitigate climacteric symptoms but may also modulate the aging process itself. Central to these effects are effects of CRE on the metabolic key regulator, the AMP-activated protein kinase (AMPK).

CONCLUSIONS

As an extension of this effect dimension, other off-label indications may appear attractive in the sense of repurposing of this herbal treatment.

Hispidulin Ameliorates Endotoxin-Induced Acute Kidney Injury in Mice

Lipopolysaccharide (LPS) is an endotoxin that plays a crucial role in septic acute kidney injury (AKI). Hispidulin is a natural flavonoid that possesses various biological activities. Recent studies have shown that hispidulin administration alleviates various inflammatory diseases in animal models. This study aimed to investigate the renoprotective effect of hispidulin on LPS-induced AKI. Male C57BL/6 mice were administered LPS (10 mg/kg) with or without hispidulin (50 mg/kg). Hispidulin administration attenuated renal dysfunction, histological alterations, and the upregulation of neutrophil gelatinase-associated lipocalin. This flavonoid also reduced cytokine production and Toll-like receptor 4 expression, inhibited nuclear factor-κB and mitogen-activated protein kinase cascades, and alleviated immune cell infiltration. The oxidation of lipids and DNA was also inhibited by hispidulin administration. This antioxidant effect of hispidulin was associated with the downregulation of NADPH oxidase 4, the activation of catalase and superoxide dismutase activities, and the restoration of glutathione levels. Moreover, hispidulin administration attenuated tubular cell apoptosis by inhibiting caspase-3 pathway. These data suggest that hispidulin ameliorates endotoxin-induced kidney injury by suppressing inflammation, oxidative stress, and tubular cell death.

Re-appraising the role of flavonols, flavones and flavonones on osteoblasts and osteoclasts- A review on its molecular mode of action

Bone disorders have become a global concern illustrated with decreased bone mineral density and disruption in microarchitecture of natural bone tissue organization. Natural compounds that promote bone health by augmenting osteoblast functions and suppressing osteoclast functions has gained much attention and offer greater therapeutic value compared to conventional therapies. Amongst several plant-based molecules, flavonoids act as a major combatant in promoting bone health through their multi-faceted biological activities such as antioxidant, anti-inflammatory, and osteogenic properties. They protect bone loss by regulating the signalling cascades involved in osteoblast and osteoclast functions. Flavonoids augment osteoblastogenesis and inhibits osteoclastogenesis through their modulation of various signalling pathways. This review discusses the role of various flavonoids and their molecular mechanisms involved in maintaining bone health by regulating osteoblast and osteoclast functions.

Combined Anti-Adipogenic Effects of Hispidulin and p-Synephrine on 3T3-L1 Adipocytes

Hispidulin is abundant in Arrabidaea chica, Crossostephium chinense, and Grindelia argentina, among others. p-Synephrine is the main phytochemical constituent of Citrus aurantium. It has been used in combination with various other phytochemicals to determine synergistic effects in studies involving human participants. However, there have been no reports comparing the anti-adipogenic effects of the combination of hispidulin and p-synephrine. The current study explores the anti-adipogenic effects of hispidulin alone and in combination with p-synephrine in a murine preadipocyte cell line, 3T3-L1. Co-treatment resulted in a greater inhibition of the formation of red-labeled lipid droplets than the hispidulin or p-synephrine-alone treatments. Co-treatment with hispidulin and p-synephrine also significantly inhibited adipogenic marker proteins, including Akt, mitogen-activated protein kinases, peroxisome proliferator-activated receptor gamma, CCAAT/enhancer-binding protein alpha, glucocorticoid receptor, and CCAAT/enhancer-binding protein β. Although further studies are required to assess the effects of each drug on pharmacokinetic parameters, a combination treatment with hispidulin and p-synephrine may be a potential alternative strategy for developing novel anti-obesity drugs.

The Effect of Hispidulin, a Flavonoid from Salvia plebeia, on Human Nasopharyngeal Carcinoma CNE-2Z Cell Proliferation, Migration, Invasion, and Apoptosis

Nasopharyngeal carcinoma (NPC) is a common malignant head and neck tumor. Drug resistance and distant metastasis are the predominant cause of treatment failure in NPC patients. Hispidulin is a flavonoid extracted from the bioassay-guided separation of the EtOH extract of Salvia plebeia with strong anti-proliferative activity in nasopharyngeal carcinoma cells (CNE-2Z). In this study, the effects of hispidulin on proliferation, invasion, migration, and apoptosis were investigated in CNE-2Z cells. The [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) assay and the colony formation assay revealed that hispidulin could inhibit CNE-2Z cell proliferation. Hispidulin (25, 50, 100 μM) also induced apoptosis in a dose-dependent manner in CNE-2Z cells. The expression of Akt was reduced, and the expression of the ratio of Bax/Bcl-2 was increased. In addition, scratch wound and transwell assays proved that hispidulin (6.25, 12.5, 25 μM) could inhibited the migration and invasion in CNE-2Z cells. The expressions of HIF-1α, MMP-9, and MMP-2 were decreased, while the MMPs inhibitor TIMP1 was enhanced by hispidulin. Moreover, hispidulin exhibited potent suppression tumor growth and low toxicity in CNE-2Z cancer-bearing mice at a dosage of 20 mg/kg/day. Thus, hispidulin appears to be a potentially effective agent for NPC treatment.

Hispidulin modulates epithelial-mesenchymal transition in breast cancer cells

Breast cancer is the most commonly diagnosed cancer worldwide. Despite the use of chemotherapeutic drugs, drug resistance has been observed in numerous patients with breast cancer. Epithelial-mesenchymal transition (EMT) is an important initiation step in the process of metastasis, whereby cancer cells move away from the original tumor site. Therefore, the discovery of new substances that suppress EMT is a promising avenue for cancer treatment. The present study investigated the effect of hispidulin, a polyphenolic flavonoid, on EMT in human breast cancer cells in vitro (MCF-7 and HCC38). The EMT-associated mRNA and protein expression levels were measured using reverse transcription-quantitative PCR or western blot analysis. Hispidulin treatment increased the expression levels of EMT-associated epithelial markers and decreased the expression levels of mesenchymal markers in both cells. Transforming growth factor-β1 (TGF-β1) treatment increased breast cancer cell viability (assessed via MTS assay) and EMT induction. However, hispidulin and TGF-β1 co-treatment increased the expression levels of E-cadherin and occludin, while downregulating vimentin expression. Additionally, hispidulin treatment inhibited TGF-β1-induced Smad2/3 signaling and cell migration in both breast cancer cell lines. Overall, the current findings suggested that hispidulin may inhibit EMT and cell migration by suppressing the Smad2/3 signaling pathway in breast cancer cells.

Genipin and insulin combined treatment improves implant osseointegration in type 2 diabetic rats

BACKGROUND

Type 2 diabetes mellitus (T2DM) has a harmful effect on the stability and osseointegration of dental implants. T2DM induces mitochondrial damage by inhibiting AMPK signaling, resulting in oxidative stress and poor osteogenesis in the peri-implant bone area. Genipin is a major component of gardenia fruits with strong antioxidant, anti-inflammation, and antidiabetic actions, and it also can activate mitochondrial quality control via the AMPK pathway. The purpose of this study was to investigate the effects of genipin and insulin treatment on implant osseointegration in T2DM rats and explore the underlying mechanisms.

METHODS

Streptozotocin-induced diabetic rats received implant surgery in their femurs and were then assigned to five groups that were subjected to different treatments for three months: control group, T2DM group, insulin-treated T2DM group (10 IU/kg), genipin-treated T2DM group (50 mg/kg), and the genipin and insulin combination-treated T2DM group. Then, we regularly assessed the weight and glucose levels of the animals. Rats were euthanized at 3 months after the implantation procedure, and the femora were harvested for microscopic computerized tomography analysis, biomechanical tests, and different histomorphometric assessment.

RESULTS

The results indicated that the highest blood glucose and oxidative stress levels were measured for the T2DM group, resulting in the poorest osseointegration. The combination-treated T2DM group mitigated hyperglycemia and normalized, reactivated AMPK signaling, and alleviated oxidative stress as well as reversed the negative effect of osseointegration. There were beneficial changes observed in the T2DM-genipin and T2DM-insulin groups, but these were less in comparison to the combination treatment group.

CONCLUSION

Our study suggests that treatment with genipin in combination with insulin could be an effective method for promoting implant osseointegration in T2DM rats, which may be related to AMPK signaling.

Potential Molecular Mechanisms of Plantain in the Treatment of Gout and Hyperuricemia Based on Network Pharmacology

BACKGROUND

The incidence of gout and hyperuricemia is increasing year by year in the world. Plantain is a traditional natural medicine commonly used in the treatment of gout and hyperuricemia, but the molecular mechanism of its active compounds is still unclear. Based on network pharmacology, this article predicts the targets and pathways of effective components of plantain for gout and hyperuricemia and provides effective reference for clinical medication.

METHOD

Traditional Chinese medicine systems pharmacology database and analysis platform (TCMSP) and SymMap databases were used to screen out the active compounds and their targets in plantain. GeneCards, Therapeutic Target Database (TTD), and Online Mendelian Inheritance in Man (OMIM) databases were used to find the targets corresponding to gout and hyperuricemia. Venn diagram was used to obtain the intersection targets of plantain and diseases. The interaction network of the plantain active compounds-targets-pathways-diseases was constructed by using Cytoscape 3.7.2 software. Finally, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were carried out.

RESULT

Seven active compounds were identified by network pharmacological analysis, including dinatin, baicalein, baicalin, sitosterol, 6-OH-luteolin, stigmasterol, and luteolin. Plantain plays a role in gout and hyperuricemia diseases by regulating various biological processes, cellular components, and molecular functions. The core targets of plantain for treating gout are MAPK1, RELA, TNF, NFKBIA, and IFNG, and the key pathways are pathways in cancer, hypoxia-inducible factor-1 (HIF-1) signaling pathway, interleukin (IL)-17 signaling pathway, Chagas disease (American trypanosomiasis), and relaxin signaling pathway. The core targets of plantain for hyperuricemia are RELA, MAPK1, NFKBIA, CASP3, CASP8, and TNF, and the main pathways are pathways in cancer, apoptosis, hepatitis B, IL-17 signaling pathway, and toxoplasmosis.

CONCLUSION

This study explored the related targets and mechanisms of plantain for the treatment of gout and hyperuricemia from the perspective of network pharmacological analysis, reflecting the characteristics of multiple components, multiple targets, and multiple pathways, and it provides a good theoretical basis for the clinical application of plantain.

Hispidulin: A novel natural compound with therapeutic potential against human cancers

Cancer is one of the most devastating disease and leading cause of death worldwide. The conventional anticancer drugs are monotarget, toxic, expensive and suffer from drug resistance. Development of multi-targeted drugs from natural products has emerged as a new paradigm to overcome aforementioned conventionally encountered obstacles. Hispidulin (HIS), is a biologically active natural flavone with versatile biological and pharmacological activities. The anticancer, antimutagenic, antioxidative and anti-inflammatory properties of HIS have been reported. The aim of this review is to summarize the findings of several studies over the last few decades on the anticancer activity of HIS published in various databases including PubMed, Google Scholar, and Scopus. HIS has been shown to reduce the growth of cancer cells by inducing apoptosis, arresting cell cycle, inhibiting angiogenesis, invasion and metastasis via modulating multiple signaling pathways implicated in cancer initiation and progression. Multitargeted anticancer activity of HIS remains the strongest point for developing it into potential anticancer drug. We also highlighted the natural sources, anticancer mechanism, cellular targets, and chemo-sensitizing potential of HIS. This review will provide bases for design and conduct of further pre-clinical and clinical trials to develop HIS into a lead structure for future anticancer therapy.

Hispidulin: A promising flavonoid with diverse anti-cancer properties

In recent years, natural products have increasingly attracted more attention because of their potential anticancer activity and low intrinsic toxicity. Hispidulin is a natural flavonoid with a wide range of biological activities, including anti-inflammatory, antifungal, antiplatelet, anticonvulsant, anti-osteoporotic, and notably anticancer activities. Numerous in vivo and in vitro studies have shown that hispidulin, as a potential anticancer drug, affects cell proliferation, apoptosis, cell cycle, angiogenesis, and metastasis. Moreover, hispidulin exhibits synergistic anti-tumor effects when combined with some common clinical anticancer drugs (e.g., gemcitabine, 5-fluoroucil, sunitinib, temozolomide, and TRAIL). The combination of hispidulin and chemotherapeutic drugs reduces the efflux of chemotherapeutic drugs, enhances the chemosensitivity of cancer cells, and reverses drug resistance. Herein, we outlined the anticancer effects of hispidulin in various cancers and its intracellular molecular targets and related mechanisms of its anticancer activity. Based on the available literature, it can be established that hispidulin has significant potential to become an important complementary medicine for cancer prevention and treatment. However, more in-depth in vitro and in vivo studies should be conducted to support its translation from bench to bedside.

Hispidulin exhibits potent anticancer activity in vitro and in vivo through activating ER stress in non‑small‑cell lung cancer cells

Hispidulin is a medicinal natural compound isolated from S. involucrata, which exhibits potent anticancer properties. However, there are few reports on its effects on lung cancer cells. Therefore, the current study investigated the effects of hispidulin on cell viability and apoptosis in human non‑small‑cell lung cancer (NSCLC) cell lines NCI‑H460 and A549 in vitro and in vivo. Methyl thiazolyl tetrazolium, colony formation assay, Hoechst 33342 staining, flow cytometry and western blotting were performed on Human NCI‑H460 and A549 cells. A mouse xenograft model was also established using NCI‑H460 cells. The results showed that the growth of NCI‑H460 and A549 cells was inhibited, while apoptosis was promoted by hispidulin via increased generation of reactive oxygen species (ROS) in a dose‑dependent manner. Furthermore, hispidulin triggered apoptosis in NSCLC cells through upregulating the expression of cleaved caspase‑3 and cleaved poly [ADP‑ribose] polymerase. All these effects were reversed upon pretreatment with glutathione, a selective ROS inhibitor. In addition, endoplasmic reticulum stress (ER stress) in NCI‑H460 cells was activated by hispidulin. Pretreatment with tauroursodeoxycholic acid, a specific ER stress inhibitor, effectively reduced the cell apoptosis induced by hispidulin. In conclusion, hispidulin induces ROS‑mediated apoptosis via activating the ER stress pathway. The current study provides theoretical basis for the antitumor effect of hispidulin in NSCLC.

Flavone Hispidulin Stimulates Glucagon-Like Peptide-1 Secretion and Ameliorates Hyperglycemia in Streptozotocin-Induced Diabetic Mice

SCOPE

Loss of functional β-cell mass is central for the deterioration of glycemic control in diabetes. The incretin hormone glucagon-like peptide-1 (GLP-1) plays a critical role in maintaining glycemic homeostasis via potentiating glucose-stimulated insulin secretion and promoting β-cell mass. Agents that can directly promote GLP-1 secretion, thereby increasing insulin secretion and preserving β-cell mass, hold great potential for the treatment of T2D.

METHODS AND RESULTS

GluTag L-cells, INS832/13 cells, and mouse ileum crypts and islets are cultured for examining the effects of flavone hispidulin on GLP-1 and insulin secretion. Mouse livers and isolated hepatocytes are used for gluconeogenesis. Streptozotocin-induced diabetic mice are treated with hispidulin (20 mg kg^-1 day^-1 , oral gavage) for 6 weeks to evaluate its anti-diabetic potential. Hispidulin stimulates GLP-1 secretion from the L-cell line, ileum crypts, and in vivo. This hispidulin action is mediated via activation of cyclic adenosine monophosphate/protein kinase A signaling. Hispidulin significantly improves glycemic control in diabetic mice, concomitant with improved insulin release, and β-cell survival. Additionally, hispidulin decreases hepatic pyruvate carboxylase expression in diabetic mice and suppresses gluconeogenesis in hepatocytes. Furthermore, hispidulin stimulates insulin secretion from β-cells.

CONCLUSION

These findings suggest that Hispidulin may be a novel dual-action anti-diabetic compound via stimulating GLP-1 secretion and suppressing hepatic glucose production.

Saussureae Involucratae Herba (Snow Lotus): Review of Chemical Compositions and Pharmacological Properties

Saussureae Involucratae Herba is the dried ground part of Saussurea involucrata (Kar. et Kir.) Sch.-Bip, which is also named as “Snow lotus” and being used in traditional Uyghur and/or Chinese medicine. This rare herb can be found at 4,000 m elevation in western part of Tianshan Mountain, Xinjiang China. According to China Pharmacopoeia (2015), the major pharmaceutical values of “Snow lotus” (Xuě liánhuā in Chinese) are alleviating rheumatoid arthritis, accelerating blood circulation and mitigating other “cold” syndromes. Traditionally, the clinical application of “Snow lotus” includes the treatments in inflammation-associated disorder, blood circulation acceleration and heat and dampness elimination. Recent studies suggested that “Snow lotus” possessed therapeutic effects associating with anti-cancer, anti-oxidation, adipogenesis suppression and neuroprotection activities, which were proposed to be related with its bioactive constitutes, i.e. acacetin, hispidulin, and rutin. In the present review, we aim to summarize pharmacological effects and underlying cell signaling pathways of “Snow lotus” in treating various medical problems.

Activation of Dusp14 protects against osteoclast generation and bone loss by regulating AMPKα-dependent manner

Osteoporosis is a progressive systematic skeletal disorder featured by decreased bone and enhanced risk of fracture due to an uncoupling of bone resorption. Chronic inflammatory response plays an essential role in osteoporosis progression. Unfortunately, the pathogenesis that contributes to osteoporosis still remains unclear. Dual-specificity phosphatase 14 (Dusp14, also known as MKP6) is a MAP kinase phosphatase, and has important roles in regulating various cellular processes. In the study, we attempted to explore the effects of Dusp14 on osteoporosis development. The results indicated that Dusp14 expression was decreased during osteoclast differentiation and that Dusp14 over-expression markedly alleviated osteoclast generation regulated by macrophage colony-stimulating factor (M-CSF) and receptor activator of NF-κB ligand (RANKL). In M-CSF/RANKL-treated bone marrow-derived cells (BMMs), promoting Dusp14 expression significantly alleviated inflammation and apoptosis by suppressing nuclear factor (NF)-κB and Caspase-3 signaling pathways, respectively. Furthermore, AMP-activated protein kinase (AMPK)-α activation was markedly increased by Dusp14 over-expression in M-CSF/RANKL-incubated BMMs. Importantly, we found that AMPKα blockage obviously abolished the role of Dusp14 in preventing osteoclasts differentiation at least partly via elevating M-CSF/RANKL-elicited inflammation and apoptosis. In vivo, magnesium silicate-induced inflammatory osteoporosis was obviously alleviated in Dusp14 transgenic (TG) mice. Taken together, we defined Dusp14 as an important molecular switch resulting in osteoporosis through an AMPKα-dependent manner.

Antimicrobial, Antioxidant Activities, and HPLC Determination of the Major Components of Verbena carolina (Verbenaceae)

Verbena carolina L. (Verbenaceae) is used as a decoction in Mexican folk medicine with applications against digestive problems and for dermatological infections. The present work firstly reported HPLC analysis, as well as the free radical scavenging capacity of the extracts and isolated compounds. Antimicrobial analyses of these substances against the bacteria Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Salmonella typhi and the fungi Candida albicans, Trichophyton mentagrophytes and T. rubrum were also tested, as well as the acute oral toxicity in mice of aqueous extracts. Major secondary metabolites in V. carolina extracts were isolated by conventional phytochemical methods which consisted of three terpenoids ((1), (3) and (4)) and four phenolic compounds ((2), (4)-(6)). Their contents were determined by HPLC in six different samples from different locations. The results indicated that ursolic acid (1), hispidulin (2), verbenaline (3), hastatoside (4), verbascoside (5), hispidulin 7-O-β-d-glucuronopyranoside (6) and pectolinaringenin-7-O-α-d-glucuronopyranoside (7) were the main constituents and ranged from 0.17 to 3.37 mg/g of dried plant, with verbascoside being the most abundant and with a significant antioxidant activity in reactive oxygen species (ROS). Hispidulin was the only active compound against T. mentagrophytes and T. rubrum. The aqueous extract showed no significant toxicity (LD₅₀: > 5000 mg/mL). To our knowledge, this is the first comprehensive report of the chemical characterization of V. carolina and also of the activity of its constituents towards reactive oxygen species and dermatophytes, and its safety for consumption.

Hispidulin induces ER stress-mediated apoptosis in human hepatocellular carcinoma cells in vitro and in vivo by activating AMPK signaling pathway

Hispidulin (4',5,7-trihydroxy-6-methoxyflavone) is a phenolic flavonoid isolated from the medicinal plant S. involucrata, which exhibits anti-neoplastic activity against several types of cancer. However, the mechanism underlying its anti-cancer activity against hepatocellular carcinoma (HCC) has not been fully elucidated. In this study, we investigated whether and how hispidulin-induced apoptosis of human HCC cells in vitro and in vivo. We showed that hispidulin (10, 20 μmol/L) dose-dependently inhibited cell growth and promoted apoptosis through mitochondrial apoptosis pathway in human HCC SMMC7721 cells and Huh7 cells. More importantly, we revealed that its pro-apoptotic effects depended on endoplasmic reticulum stress (ERS) and unfolded protein response (UPR), as pretreatment with salubrinal, a selective ERS inhibitor, or shRNA targeting a UPR protein CHOP effectively abrogated hispidulin-induced cell apoptosis. Furthermore, we showed that hispidulin-induced apoptosis was mediated by activation of AMPK/mTOR signaling pathway as pretreatment with Compound C, an AMPK inhibitor, or AMPK-targeting siRNA reversed the pro-apoptotic effect of hispidulin. In HCC xenograft nude mice, administration of hispidulin (25, 50 mg/kg every day, ip, for 27 days) dose-dependently suppressed the tumor growth, accompanied by inducing ERS and apoptosis in tumor tissue. Taken together, our results demonstrate that hispidulin induces ERS-mediated apoptosis in HCC cells via activating the AMPK/mTOR pathway. This study provides new insights into the anti-tumor activity of hispidulin in HCC.

Hispidulin alleviates high-glucose-induced podocyte injury by regulating protective autophagy

OBJECTIVES

Diabetic nephropathy (DN) is one of the most common complications in patients with diabetes, and the discovery of novel targeted therapeutic approaches for DN treatment still faces severe challenges. In the current study, we aimed to discover a novel natural product for potential DN treatment and determine its molecular mechanisms.

MATERIALS AND METHODS

Methylthiazoltetrazolium (MTT) assay was employed to evaluate cell viability. Transmission electron microscopy, GFP-LC3 fluorescence fusion plasmid, and Annexin V/PI apoptosis assay were carried out to determine cellular autophagy and apoptosis. Moreover, quantitative proteomics and bioinformatics analysis, Western blotting, and RNA interference were performed to investigate potential molecular mechanisms.

RESULTS

Hispidulin displayed protective capacity on the high-glucose-induced podocyte injury models by activating autophagy and inhibiting apoptosis. The mechanism for hispidulin-induced autophagy was associated to Pim1 inhibition and the regulation of Pim1-p21-mTOR signaling axis. Moreover, quantitative proteomics and bioinformatics analysis revealed that the hispidulin-regulated Pim1 inhibition was associated to RAB18, NRas, PARK7, and FIS1.

CONCLUSIONS

These results indicate that hispidulin induces autophagy and inhibits apoptosis induced by high glucose in murine podocytes. This study will illuminate future developments in DN-targeted therapy.

Hispidulin suppresses cell growth and metastasis by targeting PIM1 through JAK2/STAT3 signaling in colorectal cancer

Colorectal cancer (CRC) accounts for over 600 000 deaths annually worldwide. The current study aims to evaluate the value of proto‐oncogene PIM1 as a therapeutic target in CRC and investigate the anticancer activity of hispidulin, a naturally occurring phenolic flavonoid compound, against CRC. Immunohistochemistry analysis showed that PIM1 was upregulated in CRC tissue. The role of PIM1 as an oncogene was evidenced by the fact that PIM1 knockdown inhibits cell growth, induces apoptosis, and suppresses invasion. Our results showed that hispidulin exerts antitumor activity in CRC through inhibiting the expression of PIM1. Moreover, our findings revealed that hispidulin downregulated the expression of PIM1 by inhibiting JAK2/STAT3 signaling by generating reactive oxygen species. Furthermore, our in vivo studies showed that hispidulin can significantly inhibit tumor growth and metastasis in CRC. Collectively, our results provide an experimental basis for trialing hispidulin in CRC treatment. PIM1 can be considered a potential therapeutic target in CRC.

Hispidulin mediates apoptosis in human renal cell carcinoma by inducing ceramide accumulation

Hispidulin, a polyphenolic flavonoid extracted from the traditional Chinese medicinal plant S involucrata, exhibits anti-tumor effects in a wide array of human cancer cells, mainly through growth inhibition, apoptosis induction and cell cycle arrest. However, its precise anticancer mechanisms remain unclear. In this study, we investigated the molecular mechanisms that contribute to hispidulin-induced apoptosis of human clear-cell renal cell carcinoma (ccRCC) lines Caki-2 and ACHN. Hispidulin (10, 20 μmol/L) decreased the viability of ccRCC cells in dose- and time-dependent manners without affecting that of normal tubular epithelial cells. Moreover, hispidulin treatment dose-dependently increased the levels of cleaved caspase-8 and caspase-9, but the inhibitors of caspase-8 and caspase-9 only partly abrogated hispidulin-induced apoptosis, suggesting that hispidulin triggered apoptosis via both extrinsic and intrinsic pathways. Moreover, hispidulin treatment significantly inhibited the activity of sphingosine kinase 1 (SphK1) and consequently promoted ceramide accumulation, thus leading to apoptosis of the cancer cells, whereas pretreatment with K6PC-5, an activator of SphK1, or overexpression of SphK1 significantly attenuated the anti-proliferative and pro-apoptotic effects of hispidulin. In addition, hispidulin treatment dose-dependently activated ROS/JNK signaling and led to cell apoptosis. We further demonstrated in Caki-2 xenograft nude mice that injection of hispidulin (20, 40 mg·kg^-1·d^-1, ip) dose-dependently suppressed tumor growth accompanied by decreased SphK1 activity and increased ceramide accumulation in tumor tissues. Our findings reveal a new explanation for the anti-tumor mechanisms of hispidulin, and suggest that SphK1 and ceramide may serve as potential therapeutic targets for the treatment of ccRCC.

Molecular signaling mechanisms behind polyphenol-induced bone anabolism

For millennia, in the different cultures all over the world, plants have been extensively used as a source of therapeutic agents with wide-ranging medicinal applications, thus becoming part of a rational clinical and pharmacological investigation over the years. As bioactive molecules, plant-derived polyphenols have been demonstrated to exert many effects on human health by acting on different biological systems, thus their therapeutic potential would represent a novel approach on which natural product-based drug discovery and development could be based in the future. Many reports have provided evidence for the benefits derived from the dietary supplementation of polyphenols in the prevention and treatment of osteoporosis. Polyphenols are able to protect the bone, thanks to their antioxidant properties, as well as their anti-inflammatory actions by involving diverse signaling pathways, thus leading to bone anabolic effects and decreased bone resorption. This review is meant to summarize the research works performed so far, by elucidating the molecular mechanisms of action of polyphenols in a bone regeneration context, aiming at a better understanding of a possible application in the development of medical devices for bone tissue regeneration.

Medicinal importance, pharmacological activities, and analytical aspects of hispidulin: A concise report

Herbal medicines have been played an important role in the human civilization since very ancient time as a food, cloth, medicine and other aspects. Some of the important drugs in the modern medicine were derived from the natural sources such as aspirin, digitalis, quinine, vincristine, vinblastine etc. Hispidulin (4', 5, 7-trihydroxy-6-methoxyflavone) is a flavones derivative found in plant such as Grindelia argentina, Arrabidaea chica, Saussurea involucrate, Crossostephium chinense, Artemisia and Salvia species. Hispidulin have antioxidant, antifungal, anti-inflammatory, antimutagenic, and antineoplastic properties. So far, various analytical methods have been investigated and developed for detection of hispidulin in the plant materials. Productions of hispidulin through different tissue culture techniques have been also investigated. Present review summarized medicinal uses, pharmacological activities and analytical aspects of hispidulin. From the above mentioned aspects, we can conclude that, this review will be helpful to the researcher in the field of natural product for the development of novel molecule for the treatment of different disorders.

New Role of Hispidulin in Lipid Metabolism: PPARα Activator

Hispidulin is a naturally occurring flavonoid isolated from a traditional Chinese medicinal herb, Saussurea involucrata. In this study, the regulating role of hispidulin on the mRNA expression level of enzymes involved in lipid metabolism was examined in vitro and in vivo. Moreover, the in vivo lipid-modulating effect of hispidulin was compared with that of fenofibrate, a classical PPARα agonist. Our results in present study demonstrated that hispidulin can directly bind to and activate PPARα as an agonist and thus modulate the downstream lipid-metabolizing genes. Moreover, hispidulin could attenuate dyslipidemia in high fat diet induced dyslipidemia rat model. Although further studies are needed, this study provided evidence for the potential use of hispidulin in dyslipidemia management.

UHPLC-MS-based metabolomics analysis on mice bearing neoplasm (H22) for hispidulin

Although some physiological and pathological function parameters of hepatitis and liver cancer have been investigated in relation to hispidulin (5,7,4'-trihydroxy-6-methoxyflavone), the changes of small metabolites in biofluids have been reported rarely. Recent research has shown that metabolic profiling with ultra-high-performance liquid chromatography coupled to quadrupole time of flight mass spectrometry (UHPLC-QTOF/MS) coupled with multivariate statistical analysis provides a good understanding of hispidulin effects on mice vaccinated intraperitoneally with H22 tumor cells. Twenty-five potential biomarkers, up- or down-regulated (P<0.05 or 0.01), were identified, and 17 metabolic pathways were constructed. These potential biomarkers underpin the metabolic pathways, which are disturbed in the mice bearing neoplasm (H22). These pathways include pantothenate and CoA biosynthesis; glycine, serine and threonine metabolism; nicotinate and nicotinamide metabolism; steroid hormone biosynthesis; pyrimidine metabolism; and glyoxylate and dicarboxylate metabolism. Furthermore, 4-phosphopantothenoylcysteine, glycine, niacinamide, cortisol, uracil and 5-thymidylic acid are potential biomarkers that may explain the link between hispidulin and the metabolism of mice bearing neoplasm (H22). Most of the potential biomarkers related to the function of TCA (tricarboxylic acid cycle). The rise of potential biomarkers in the drug groups promoted the up-regulation of TCA cycle compared with the model group.

Total Synthesis of Hispidulin and the Structural Basis for Its Inhibition of Proto-oncogene Kinase Pim-1

A new method is applied to synthesize hispidulin, a natural flavone with a broad spectrum of biological activities. Hispidulin exhibits inhibitory activity against the oncogenic protein kinase Pim-1. Crystallographic analysis of Pim-1 bound to hispidulin reveals a binding mode distinct from that of quercetin, suggesting that the binding potency of flavonoids is determined by their hydrogen-bonding interactions with the hinge region of the kinase. Overall, this work may facilitate construction of a library of hispidulin-derived compounds for investigating the structure-activity relationship of flavone-based Pim-1 inhibitors.

Hispidulin, a constituent of Clerodendrum inerme that remitted motor tics, alleviated methamphetamine-induced hyperlocomotion without motor impairment in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Previously, we found a patient with an intractable motor tic disorder that could be ameliorated by the ground leaf juice of Clerodendrum inerme (CI). Furthermore, the ethanol extract of CI leaves effectively ameliorated methamphetamine-induced hyperlocomotion (MIH) in mice, an animal model mimicking the hyper-dopaminergic status of tic disorders/Tourette syndrome, schizophrenia, or obsessive-compulsive disorder. Here, we for the first time identified a constituent able to reduce MIH from the CI ethanol extract that might represent a novel lead for the treatment of such disorders.

MATERIALS AND METHODS

The ethanol extract of CI was sub-divided into n-hexane, dichloromethane, n-butanol and water fractions. Using MIH alleviation as a bioassay, active compounds were identified in these fractions using silica gel chromatography, recrystallization and proton NMR spectroscopy.

RESULTS

The dichloromethane and n-hexane fractions were active in the bioassay. Further subfractionation and re-crystallization resulted in an active compound that was identified to be hispidulin by proton NMR spectroscopy. Hispidulin significantly alleviated MIH in mice at doses that did not affect their spontaneous locomotor activity or performance in the rotarod test, a measure for motor coordination.

CONCLUSIONS

Hispidulin is a flavonoid that has been isolated from several plants and reported to have anti-oxidative, anti-inflammatory and anti-cancer activities. Here, we for the very first time found that hispidulin can also alleviate MIH at doses that did not impair motor activity, suggesting a therapeutic potential of hispidulin in hyper-dopaminergic disorders.

Genistein inhibits glucocorticoid amplification in adipose tissue by suppression of 11β-hydroxysteroid dehydrogenase type 1

Excess glucocorticoids promote visceral obesity, hyperlipidemia, and insulin resistance. The main regulator of intracellular glucocorticoid levels is 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), which converts inactive glucocorticoids into bioactive forms such as cortisol in humans and corticosterone in rodents. Hexose-6-phosphate dehydrogenase (H6PD), which is colocalized with 11β-HSD1 in the intralumen of the endoplasmic reticulum, supplies a crucial coenzyme, NADPH, for full reductase activity of 11β-HSD1. Therefore, it is possible that inhibition of 11β-HSD1 will become a considerable medical treatment for metabolic diseases including obesity and diabetes. Genistein, a soy isoflavone, has received attention for its therapeutic potential for obesity, diabetes, and cardiovascular disease, and has been proposed as a promising compound for the treatment of metabolic disorders. However, the mechanisms underlying the pleiotropic anti-obesity effects of genistein have not been fully clarified. Here, we demonstrate that genistein was able to inhibit 11β-HSD1 and H6PD activities within 10 or 20min, in dose- and time-dependent manners. Inhibition of 11β-HSD2 activity was not observed in rat kidney microsomes. The inhibition was not reversed by two estrogen receptor antagonists, tamoxifen and ICI182,780. A kinetic study revealed that genistein acted as a non-competitive inhibitor of 11β-HSD1, and its apparent Km value for 11-dehydrocorticosterone was 0.5μM. Genistein also acted as a non-competitive inhibitor of H6PD, and its apparent Km values for G6P and NADP were 0.9 and 3.3μM, respectively. These results suggest that genistein may exert its inhibitory effect by interacting with these enzymes.