Effect of Pulicaria mauritanica on Glucose Metabolism and Glycogen Content in Streptozotocin-Induced Diabetic Rats.

AIMS: The study aimed to assess the antihyperglycemic activity of Pulicaria mauritanica. BACKGROUND: Pulicaria mauritanica is a medicinal and aromatic plant used for the treatment of many diseases such as inflammation, diabetes, and intestinal disorders. OBJECTIVE: The main goals of this present paper were to confirm the antihyperglycemic capacity of aqueous extract from Pulicaria mauritanica in normoglycemic and diabetic rats over a period of time (7 days of treatment). METHODS: The effect of the aqueous extract of Pulicaria mauritanica from aerial parts (AEPM) on glucose and lipid metabolism was tested using an acute test (single dose during 6 hours) and subchronic assay (repeated oral administration for seven days) at a dose of 60 mg/kg and the serum glucose levels were measured in normoglycemic and streptozotocin(STZ)-induced diabetic rats. In addition, the glycogen content in the liver, extensor digitorum longus (EDL), and soleus was evaluated. The antioxidant activity, phytochemical screening, and quantification of some secondary metabolites of this extract were also performed. RESULTS: AEPM at a dose of 60 mg/kg reduced the plasma glucose concentrations significantly in STZ-induced diabetic rats after a single oral administration (p<0.05). This lowering effect became more significant during the repeated oral administration in hyperglycemic rats (p<0.0001). Also, the findings showed that this plant exhibited a significant increase in liver and skeletal soleus muscle glycogen content in diabetic rats. AEPM revealed a remarkable antioxidant activity in addition to the presence of polyphenol compounds such as flavonoids, tannins, saponins, sterols, glucides, terpenoids, quinones, anthraquinones, and mucilage. CONCLUSION: The study shows that AEPM exhibits antihyperglycemic activity in diabetic rats, and it increases liver and muscle glycogen content.

In Vitro Studies on the Immunomodulatory Effects of Pulicaria crispa Extract on Human THP-1 Monocytes.

BACKGROUND: Pulicaria crispa (P. crispa) is a plant from the Compositae family that exhibits antioxidant, anti-inflammatory, antibacterial, and cytotoxic activities. OBJECTIVE: The current study aimed at investigating the immunomodulatory effects of P. crispa extract in lipopolysaccharide- (LPS-) stimulated human monocytic THP-1 cells. METHODS: To induce macrophage differentiation, THP-1 cell lines were treated with phorbol-12-myristate 13-acetate, followed by exposure to LPS with or without 50 or 100 µg/ml of P. crispa extract. The following tests were employed to test the immunomodulatory effects of the extract: MTT assay, ELISA, Western blotting analysis, cell migration and phagocytosis assays, and Annexin V staining method. RESULTS: Exposure to 100 µg/ml P. crispa extract significantly reduced THP-1 cell proliferation, migration, and phagocytosis (in LPS-stimulated cells, but not in unstimulated cells). Moreover, the extract alone significantly reduced the rate of THP-1 cell apoptosis, while it increased the rate of late apoptosis. Molecular investigations showed that treatment with P. crispa extract significantly upregulated the expression of ERK1, p-MAPK, P-P38, and Bcl2, while it significantly reduced the expression of ERK5, Bax, NF-κB, P-NF-κB, CCL1, CCL2, CCL5, CCL22, CXCL1, and CXCL10. CONCLUSION: Pulicaria crispa extract exhibited anti-inflammatory, antiproliferative, antimigratory, and antiphagocytic effects in LPS-stimulated THP-1 cells. Future studies should investigate these mechanisms in animal models with chronic inflammatory diseases.

Pulicaria jaubertii E. Gamal-Eldin reduces triacylglyceride content and modifies cellular antioxidant pathways in 3T3-L1 adipocytes.

Levels of obesity in Middle Eastern countries are increasing. Phytochemicals have anti-obesogenic properties as evidenced by prevention of adipocyte differentiation and blocking triacylglyceride (TG) accumulation. In Yemen, Pulicaria jaubertii E. Gamal-Eldin (PJ) is a food additive and a traditional medicine. We tested the hypothesis that phytochemicals present in PJ inhibit adipocytic responses during differentiation of 3T3-L1 preadipocytes to adipocytes. Methanolic extracts of PJ did not block expression of fatty acid binding protein 4 (FABP4) a marker of differentiation but did inhibit TG accumulation. Treatment of 3T3-L1 preadipocytes increased NADPH:quinone oxidoreductase 1 (NQO1), a suppressor of TG accumulation. Further fractionation of the methanolic PJ extract with hexane and dichloromethane (DCM) demonstrated that bioactivity towards TG reduction and elevated expression of NQO1 and other antioxidant genes (glutamate cysteine ligase catalytic unit, glutathione disulfide reductase, glutathione peroxidase (GPx) 4 resided in the DCM fraction. Activity towards depleting GSH and elevating the expression of catalase and GPx3 were found in the DCM and hexane fractions. Analysis by gas chromatography and liquid chromatography coupled with mass spectrometry demonstrated the presence of catechin-like moieties in the DCM and methanolic fractions and suggest that these components were partially responsible for the bioactivity of these fractions. In summary, our data indicate that fractions derived PJ exhibit anti-adipogenic properties in part through the presence of catechin-like compounds.

Secondary metabolites from two species of Pulicaria and their cytotoxic activity.

Two new compounds, the sesquiterpene (1E,5E)-8ß-acetoxy-4α-hydroxy-7ßH-germacra-1(10),5-dien-14-oic acid (2), and a nor-sesquiterpene, (5E)-8ß-acetoxy-4α-hydroxy-7ßH-germacr-5-en-10-one (3), were isolated from Pulicaria canariensis ssp. lanata, along with ten known compounds, including the flavonoid 5,3'-dihydroxy-3,7,4'-trimethoxyflavone (4). From Pulicaria burchardii, we isolated seven known compounds; the physical and spectroscopic data of the triterpenoid 3ß-hydroxytaraxaster-20-en-30-al (1) are reported. The structures of compounds 1-3 were determined on the basis of HR-MS, and 1D- and 2D-NMR studies. The structure of 2 was corroborated by X-ray crystal diffraction. Cell viability experiments revealed that the semisynthetic flavonoid 4b was the most cytotoxic compound against human leukemia cells, and the cytotoxicity was caused by induction of apoptosis, as determined by microscopy of nuclear changes.