Inhibition of immediate-type allergic reactions by Prunella vulgaris in a murine model

Network Pharmacology and ­Experimental Analyses of the Mechanism of Analgesic and Glucose Intolerance Through Glucocorticoid Signaling in C57 Mice Treated with Water Extract of Prunella vulgaris L. Spica

The aim of this study was to confirm the anti-inflammatory effect and explore the adverse effects and underlying mechanisms of Prunella vulgaris L., which has been extensively used for hundreds of years in East Asia. Network pharmacology studies predicted that glucocorticoids (GCs), GC-targeting molecules, and brain-derived neurotrophic factor (BDNF) were intensively involved in the anti-inflammation and glucose intolerance. To attest the effects and underlying mechanisms, C57 male mice were randomly divided into 5 groups, control (C), dexamethasone (Dex), water extract of P. vulgaris (PE 35 or 70 mg), and PE (70 mg) + mifepristone (PEM). After a 3-week treatment, acetic acid-induced writhing and hot plate tests confirmed the peripheral and central analgesic effects, respectively. Plasma GCs and BDNF were significantly increased. Coincidently, plasma pro-inflammatory cytokines, including IL1β, IL6, and IL10, were decreased by PE treatment, which were blocked by the application of mifepristone ( P < 0.5). Western blots confirmed GC receptor (GR) translocation, and decreased cyclooxygenase 2 in the lumber spine by PE treatment. Food intake was impeded after a 4-week PE treatment, but the ratio of bodyweight gain to food intake was increased in a time-dependent manner. An intraperitoneal glucose tolerance test disclosed that PE treatment impaired glucose disposal in mice. Quantitative polymerase chain reaction (PCR) showed that hepatic GC-responsive genes such as GC-induced leucine zipper protein and glucose-6-phosphatase catalytic subunit 1 were up-regulated, and hypothalamic neuropeptide Y and agouti-related protein expressions were decreased by PE treatment. Hypothalamic BDNF was up-regulated, whereas hepatic BDNF was down-regulated. The regulation of these genes by PE was reversed by mifepristone administration. In conclusion, PE treatment plays analgesic and glucose regulation roles simultaneously through GC-induced signaling pathways, and P. vulgaris may provide a natural ligand of GR for the treatment of inflammation with glucose dysregulation.

Prunella vulgaris: A Comprehensive Review of Chemical Constituents, Pharmacological Effects and Clinical Applications

Prunella vulgaris (PV) is a perennial herb belonging to the Labiate family and is widely distributed in the northeastern Asian countries such as Korea, Japan, and China. It is reported to display diverse biological activities including anti-microbial, anti-cancer, and anti-inflammation as determined by in vitro or in vivo studies. So far, about 200 compounds have been isolated from PV plant and a majority of these have been characterized mainly as triterpenoids, sterols and flavonoids, followed by coumarins, phenylpropanoids, polysaccharides and volatile oils. This review summarizes and analyzes the current knowledge on the chemical constituents, pharmacological activities, mechanisms of action and clinical applications of the PV plant including its potential as a future medicinal plant. Although some of the chemical constituents of the PV plant and their mechanisms of action have been investigated, the biological activities of many of these remain unknown and further clinical trials are required to further enhance its reputation as a medicinal plant.

Lamiaceae: An Insight on Their Anti-Allergic Potential and Its Mechanisms of Action

The prevalence of allergic diseases such as asthma, allergic rhinitis, food allergy and atopic dermatitis has increased dramatically in recent decades. Conventional therapies for allergy can induce undesirable effects and hence patients tend to seek alternative therapies like natural compounds. Considering the fact above, there is an urgency to discover potential medicinal plants as future candidates in the development of novel anti-allergic therapeutic agents. The Lamiaceae family, or mint family, is a diverse plant family which encompasses more than 7,000 species and with a cosmopolitan distribution. A number of species from this family has been widely employed as ethnomedicine against allergic inflammatory skin diseases and allergic asthma in traditional practices. Phytochemical analysis of the Lamiaceae family has reported the presence of flavonoids, flavones, flavanones, flavonoid glycosides, monoterpenes, diterpenes, triterpenoids, essential oil and fatty acids. Numerous investigations have highlighted the anti-allergic activities of Lamiaceae species with their active principles and crude extracts. Henceforth, this review has the ultimate aim of compiling the up-to-date (2018) findings of published scientific information about the anti-allergic activities of Lamiaceae species. In addition, the botanical features, medicinal uses, chemical constituents and toxicological studies of Lamiaceae species were also documented. The method employed for data collection in this review was mainly the exploration of the PubMed, Ovid and Scopus databases. Additional research studies were obtained from the reference lists of retrieved articles. This comprehensive summarization serves as a useful resource for a better understanding of Lamiaceae species. The anti-allergic mechanisms related to Lamiaceae species are also reviewed extensively which aids in future exploration of the anti-allergic potential of Lamiaceae species.

Characterization of the inhibitory effect of an extract of Prunella vulgaris on Ebola virus glycoprotein (GP)-mediated virus entry and infection

Currently, no approved antiviral therapeutic is available for treatment or prevention of Ebola virus (EBOV) infection. In this study, we characterized an EBOV-glycoprotein (GP) pseudotyped HIV-1-based vector system in different cell cultures, including human umbilical vein endothelial cells (HUVECs) and human macrophages, for the screening of anti-EBOV-GP agent(s). Based on this system, we demonstrated that an aqueous extract (CHPV) from the Chinese herb Prunella vulgaris displayed a potent inhibitory effect on EBOV-GP pseudotyped virus (EBOV-GP-V)-mediated infection in various cell lines, including HUVEC and macrophage. In addition, our results indicated that CHPV was able to block an eGFP-expressing Zaire ebola virus (eGFP-ZEBOV) infection in VeroE6 cells. The anti-EBOV activity of CHPV was exhibited in a dose-dependent manner. At a 12.5 μg/ml concentration, the CHPV showed a greater than 80% inhibition of EBOV-GP-V and eGFP-EBOV infections. Likewise, our studies suggested that the inhibitory effect of CHPV occurred by binding directly to EBOV-GP-Vs and blocking the early viral events. Interestingly, our results have shown that CHPV was able to enhance the anti-EBOV activity of the monoclonal antibody MAb 2G4 against EBOV-GP. Overall, this study provides evidence that CHPV has anti-EBOV activity and may be developed as a novel antiviral approach against EBOV infection.

Orally administered extract from Prunella vulgaris attenuates spontaneous colitis in mdr1a-/- mice

AIM: To investigate the ability of a Prunella vulgaris (P. vulgaris) ethanolic extract to attenuate spontaneous typhlocolitis in mdr1a^-/- mice.

METHODS: Vehicle (5% ethanol) or P. vulgaris ethanolic extract (2.4 mg/d) were administered daily by oral gavage to mdr1a^-/- or wild type FVB^WT mice from 6 wk of age up to 20 wk of age. Clinical signs of disease were noted by monitoring weight loss. Mice experiencing weight loss in excess of 15% were removed from the study. At the time mice were removed from the study, blood and colon tissue were collected for analyses that included histological evaluation of lesions, inflammatory cytokine levels, and myeloperoxidase activity.

RESULTS: Administration of P. vulgaris extracts to mdr1a^-/- mice delayed onset of colitis and reduced severity of mucosal inflammation when compared to vehicle-treated mdr1a^-/- mice. Oral administration of the P. vulgaris extract resulted in reduced (P < 0.05) serum levels of IL-10 (4.6 ± 2 vs 19.4 ± 4), CXCL9 (1319.0 ± 277 vs 3901.0 ± 858), and TNFα (9.9 ± 3 vs 14.8 ± 1) as well as reduced gene expression by more than two-fold for Ccl2, Ccl20, Cxcl1, Cxcl9, IL-1α, Mmp10, VCAM-1, ICAM, IL-2, and TNFα in the colonic mucosa of mdr1a^-/- mice compared to vehicle-treated mdr1a^-/- mice. Histologically, several microscopic parameters were reduced (P < 0.05) in P. vulgaris-treated mdr1a^-/- mice, as was myeloperoxidase activity in the colon (2.49 ± 0.16 vs 3.36 ± 0.06, P < 0.05). The numbers of CD4⁺ T cells (2031.9 ± 412.1 vs 5054.5 ± 809.5) and germinal center B cells (2749.6 ± 473.7 vs 4934.0 ± 645.9) observed in the cecal tonsils of P. vulgaris-treated mdr1a^-/- were significantly reduced (P < 0.05) from vehicle-treated mdr1a^-/- mice. Vehicle-treated mdr1a^-/- mice were found to produce serum antibodies to antigens derived from members of the intestinal microbiota, indicative of severe colitis and a loss of adaptive tolerance to the members of the microbiota. These serum antibodies were greatly reduced or absent in P. vulgaris-treated mdr1a^-/- mice.

CONCLUSION: The anti-inflammatory activity of P. vulgaris ethanolic extract effectively attenuated the severity of intestinal inflammation in mdr1a^-/- mice.

Anti-Diabetic Atherosclerosis Effect of Prunella vulgaris in db/db Mice with Type 2 Diabetes

Diabetes mellitus is the leading cause of vascular complications such as atherosclerosis. This study was designed to investigate whether Prunella vulgaris (APV) would inhibit diabetic atherosclerosis in db/db mice with type 2 diabetes. The db/db mice were treated with high fat/high cholesterol (HFHC) diet and an aqueous extract of APV (100 and 200 mg/kg/day) for eight weeks to examine the long-term effect on metabolic abnormalities and diabetic atherosclerosis. APV treatment markedly lowered blood glucose and systolic blood pressure. The db/db mice experienced an increase in blood urea nitrogen as well as a decrease of creatinine clearance, the latter of which was restored by treatment with APV. Treatment with APV markedly decreased total plasma cholesterol, triglyceride, and LDL-cholesterol and also increased the HDL-cholesterol. In addition, malondialdehyde and TGF-β1 were decreased by treatment of APV. On the other hand, total NO level was decreased in db/db mice. However, the NO level was increased by treatment with APV, suggesting an association with vascular dysfunction. Vascular relaxation of aortic rings by acetylcholine or SNP-inducement was ameliorated by APV in a dose-dependent manner. Damage of vascular intima and hypertrophic of media were observed in db/db mice; however its dysfunction was improved by the treatment of APV. APV treatment significantly reduced the aortic expressions of ICAM-1, VCAM-1, ET-1, and nitrotyrosine. Furthermore, expression of eNOS in aortic was remarkably increased by APV treatment. Taken together, APV suppressed hyperglycemia and diabetic vascular dysfunction in HFHC diet-db/db mice. The present data suggest that Prunella vulgaris may prevent development of diabetic atherosclerosis.

Prunella vulgaris L. Upregulates eNOS expression in human endothelial cells

The purported effects of "circulation-improving" herbs used in traditional Chinese medicine (TCM) show striking similarities with the vascular actions of nitric oxide (NO) produced by the endothelial NO synthase (eNOS). We have previously reported that Salviae miltiorrhizae radix and Zizyphi spinosae semen upregulate eNOS expression. In the present study, we studied the effect on eNOS gene expression of 15 Chinese herbs with potential effects on the vasculature, and identified Prunella vulgaris L. (PVL) (flowering spike) as a potent eNOS-upregulating agent. In EA.hy 926 cells, a cell line derived from human umbilical vein endothelial cells (HUVEC), an aqueous extract of PVL increased eNOS promoter activity, eNOS mRNA and protein expressions, as well as NO production in concentration- and time-dependent manners. We have previously shown that ursolic acid (a constituent of Salviae miltiorrhizae radix), betulinic acid (a compound present in Zizyphi spinosae semen), luteolin and cynaroside (ingredients of artichoke, Cynara scolymus L.) are capable of enhancing eNOS gene expression. These compounds are also present in significant quantities in PVL. Thus, PVL contains active principles that stimulate human eNOS gene expression, and such compounds may have therapeutic potential against cardiovascular diseases.

Anti-anaphylactic effect of Euphorbia hirta

The Euphorbia hirta ethanolic extract (EH A001) was found to possess a prominent anti-anaphylactic activity. A preventive effect of EH-A001 given by oral route at dose from 100 to 1000 mg/kg was observed against compound 48/80-induced systemic anaphylaxis. At the same range of dose, EH-A001 inhibited passive cutaneous anaphylaxis (PCA) in rat and active paw anaphylaxis in mice. A suppressive effect of EH-A001 was observed on the release of TNF-alpha and IL-6 from anti-DNP-HSA activated rat peritoneal mast cells.

Prunella stica inhibits the proliferation but not the prostaglandin production of Ishikawa cells

Chinese herbs have been used to relieve dysmenorrhea associated with endometriosis. Active components in the herbs and their mechanisms of action remain unknown. Prunella stica, a Chinese herb commonly used to treat dysmenorrhea, was chosen for the present studies. Its effects were investigated on Ishikawa cells, an epithelial cell line derived from human endometrium. Cell proliferation and inhibition of interleukin 1beta (IL-1beta) induced prostaglandin (PG) production were examined. To learn more about the active components, 120 fractions were collected from the crude extract and each fraction was tested individually. To further characterize the active components, aliquots of fractions with activity were subject to mass spectrometry analysis. Crude extract of P. stica inhibited the proliferation of Ishikawa cells but not the IL-1beta induced PG production. Active components of P. stica clustered around fractions 64 and 92; they increased cell doubling time from 18.6 to 26.2 and 29.4h, respectively. Mass spectrometry analysis showed fractions 64 and 92 consisted of three components whose molecular weights were 337, 348 and 430 Daltons. The therapeutic effects of P. stica reside, in part, in inhibiting the proliferation of the epithelial cells derived from human endometrium. The active components are small molecules.

Effects of twoPrunella species on lymphocyte proliferation and nitric oxide production

Water extracts of Prunella vulgaris and P. laciniata have been investigated for their immunomodulatory and antiinflammatory activities concerning their effect on the mitogenic response of murine splenocytes and nitric oxide production by murine peritoneal macrophages in vitro. It was found that both extracts stimulated the proliferation of T-lymphocytes and suppressed NO production in lipopolysaccharide-stimulated macrophages dose dependently without any cytotoxicity.

Cytoprotectivity of Prunella vulgaris on doxorubicin-treated rat cardiomyocytes

The cardioprotective effect of Prunella vulgaris ethylacetate fraction (PVEF) and its constituent rosmarinic acid (RA) was evaluated on isolated rat cardiomyocytes subjected to doxorubicin-induced oxidative stress. The cytoprotectivities of PVEF and RA were concentration-dependent in the range of 0.005 to 0.05 mg/ml and the effect of PVEF correlated with the RA content. Dexrazoxan (DE), used as positive control, was less effective than PVEF or RA.

Biological activities ofPrunella vulgarisextract

The organic fraction (OF; 25.7% w/w of rosmarinic acid) of Prunella vulgaris (total extract) was found to exhibit the following: scavenging activity on diphenylpicrylhydrazyl radical (DPPH), inhibition of in vitro human LDL Cu(II)-mediated oxidation, protection of rat mitochondria and rat hepatocytes exposed to either tert-butyl hydroperoxide, or to Cu(II) and Fe(III) ions. OF also showed a potential to inhibit rat erythrocyte haemolysis and it reduced the production of LTB(4) in bovine PMNL generated by the 5-lipoxygenase pathway. Other observations included antiproliferative effects against HaCaT cells and mouse epidermal fibroblasts and a moderate OF antimicrobial activity on gram-positive bacteria. Rosmarinic, caffeic and 3-(3,4-dihydroxyphenyl)lactic acids exhibited less potent activity than the plant extract in all bioassays. The antioxidative, antimicrobial, together with antiviral effects offer good prospects for the medicinal applications of P. vulgaris.

Inhibition of immunologic and nonimmunologic stimulation-mediated anaphylactic reactions by the aqueous extract of Mentha arvensis

The effect of aqueous extract of Mentha arvensis L. var. piperascens Malinv. (Labiatae) (MAAE) on immunologic and nonimmunologic stimulation-mediated anaphylactic reactions was studied. Nonimmunologic anaphylactic reaction was induced by compound 48/80 injection. MAAE (0.005 to 0.5 g/kg) inhibited systemic anaphylactic reaction induced by compound 48/80. Immunologic anaphylactic reaction was generated by sensitizing the skin with anti-dinitrophenyl (DNP) IgE followed 48 h later with an injection of antigen. MAAE (0.001 to 1 g/kg) dose-dependently inhibited passive cutaneous anaphylaxis (PCA) when intraperitoneally, intraveneously and orally administered. MAAE (0.001 to 1 mg/ml) dose-dependently inhibited the histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80 or anti-DNP IgE. Moreover, MAAE (0.1 mg/ml) had a significant inhibitory effect on anti-DNP IgE-mediated tumor necrosis factor-alpha (TNF-alpha) production. These results indicate that MAAE inhibits immunologic and nonimmunologic stimulation-mediated anaphylactic reactions and TNF-alpha production from RPMC.