Cytotoxic and antioxidant properties of selected Scutellaria species from the Western Ghats of Peninsular India

Interactions between phenolic constituents of Scutellaria salviifolia and key targets associated with inflammation: network pharmacology, molecular docking analysis and in vitro assays

Scutellaria salviifolia Benth. (SS), an endemic plant for Turkey, is used for gastric ailments as folk medicine. In this study, we aimed to uncover the underlying molecular mechanisms with the help of network pharmacology and molecular docking analysis in the inflammation processes of gastric ailments. Gene enrichment analysis and target screening were carried out. Experimental validation was performed via cytokines of nitric oxide (NO) and interleukin-6 (IL-6) in LPS stimulated RAW 264.7 cells. Furthermore, antioxidant activity studies were performed by radical scavenging effects on different radicals. A total of 144 targets were listed for the isolated compounds where 26 of them were related to selected inflammation targets. According to the gene enrichment analysis, HIF1 signaling pathway and TNF signaling pathway were found to be involved in inflammation. We also defined AKT1, TNF, EGFR, and COX2 as key targets due to the protein-protein interactions of 26 common targets. The extract inhibited NO and IL-6 production at 100 and 200 µg/mL, while flavonoid-rich fraction possessed significant anti-inflammatory activity at the concentration of 50 and 100 µg/mL via NO and IL-6 production, respectively. It is thought that the anti-inflammatory effects of extracts, fractions and pure compounds were achieved by reducing NO and IL-6 levels via regulating the NF-κB pathway or reducing NO production by suppressing iNOS through the HIF-1 pathway when evaluated together with the results of network analysis and literature. Anti-inflammatory activities of the extract and fractions were promising and comparably with S. baicalensis, commonly used for its anti-inflammatory activity.

Phytochemical Profiling and Bio-Potentiality of Genus Scutellaria: Biomedical Approach

Scutellaria (Lamiaceae) comprises over 360 species. Based on its morphological structure of calyx, also known as Skullcap, it is herbaceous by habit and cosmopolitan by habitat. The species of Scutellaria are widely used in local communities as a natural remedy. The genus contributed over three hundred bioactive compounds mainly represented by flavonoids and phenols, chemical ingredients which serve as potential candidates for the therapy of various biological activities. Thus, the current review is an attempt to highlight the biological significance and its correlation to various isolated bioactive ingredients including flavonoids, terpenoids, phenols, alkaloids, and steroids. However, flavonoids were the dominant group observed. The findings of the Scutellaria reveal that due to its affluent basis of numerous chemical ingredients it has a diverse range of pharmacological potentials, such as antimicrobial, antioxidant, antifeedant, enzyme inhibition, anti-inflammatory, and analgesic significance. Currently, various bioactive ingredients have been investigated for various biological activities from the genus Scutellaria in vitro and in vivo. Furthermore, these data help us to highlight its biomedical application and to isolate the responsible compounds to produce innovative medications as an alternative to synthetic drugs.

Baicalein reduces hepatic fat accumulation by activating AMPK in oleic acid-induced HepG2 cells and high-fat diet-induced non-insulin-resistant mice

Nonalcoholic fatty liver disease (NAFLD) has become the most common liver disease worldwide; thus, a dietary supplement that can restrict hepatic fat accumulation is needed.

Effect of type 2 diabetes mellitus on flavonoid pharmacokinetics and tissue distribution after oral administration of Radix Scutellaria extract in rats

Radix Scutellaria is widely applied to the treatment of diabetes mellitus in China. Its main bioactive constituents contain baicalin, wogonoside, oroxyloside, and their aglycones. To investigate the effect of type 2 diabetes mellitus on both pharmacokinetics and tissue distribution of these flavonoid compounds, the six flavonoids in plasma and tissues from the normal and type 2 diabetic rats after oral administration of Radix Scutellaria extract were simultaneously measured by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method. The results showed that baicalin, wogonoside, and oroxyloside had higher C_max and AUC values (P < 0.05) in type 2 diabetic rats than that in normal rats and the tissue-distribution behaviors of the six flavonoid compounds in hearts, livers, spleens, lungs, kidneys, brains, pancreas, fat and muscle of the type 2 diabetic rats showed obviously differences from the normal rats (P < 0.05). In conclusion, the differences in the pharmacokinetics of oroxyloside and tissue distribution of the six flavanoids in Radix Scutellaria extract between diabetic and normal rats were found for the first time. The results from the present study provided a crucial basis for a better understanding of in vivo anti-diabetic mechanism of action of the six flavonoids from Radix Scutellaria.

Protective effect of Scutellaria species on AAPH-induced oxidative damage in human erythrocyte

BACKGROUND

Scutellaria baicalensis is a well-known plant in traditional Chinese medicine. Recently, several Scutellaria species with therapeutic potential have been recognized worldwide. Scutellaria colebrookiana and Scutellaria violacea, native to the Western Ghats of India, are reported to possess free radical scavenging efficacy. At present, the protective effect of these Scutellaria spp. against 2,2' azobis (2-amidinopropane) hydrochloride (AAPH)-induced oxidative damage in human erythrocytes has been analyzed.

METHODS

Oxidative stress in erythrocyte was induced by AAPH. The inhibition of hemolysis, membrane lipid peroxidation, and protein damage by chloroform extracts of Scutellaria spp. was assessed biochemically. Phytochemicals of the extracts were analyzed by Fourier transform infrared spectrophotometer (FTIR).

RESULTS

Approximately 95% of erythrocytes were lysed by AAPH over 3 h of incubation. Significant reduction in hemolysis was observed by the extracts, and the IC50 values were 18.3 and 23.5 μg/mL for S. colebrookiana and S. violacea, respectively. Both the extracts were found to inhibit AAPH-induced lipid peroxidation in ghost membrane with IC50 92±2.8 and 70±5.6 μg/mL. In the analysis of the membrane proteins using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), the AAPH-induced degradation of actin was found reduced by both the extracts. The FTIR spectrum revealed the presence of polyphenols, carboxylic acids, alkanes, and aromatic compounds in extracts. In quantitative analysis, the total polyphenolic content estimated was 380±0.23 and 203.7±1.4 mg of gallic acid equivalent per gram extract of S. colebrookiana and S. violacea.

CONCLUSIONS

Results indicate that S. colebrookiana and S. violacea are capable of protecting erythrocytes from oxidative damage. This cytoprotective effect of the extract is possibly by its antioxidant property.

Exploring therapeutic potentials of baicalin and its aglycone baicalein for hematological malignancies

Despite tremendous advances in the targeted therapy for various types of hematological malignancies with successful improvements in the survival rates, emerging resistance issues are startlingly high and novel therapeutic strategies are urgently needed. In addition, chemoprevention is currently becoming an elusive goal. Plant-derived natural products have garnered considerable attention in recent years due to the potential dual functions as chemotherapeutics and dietary chemoprevention. One of the particularly ubiquitous families is the polyphenolic flavonoids. Among them, baicalin and its aglycone baicalein have been widely investigated in hematological malignancies because both of them exhibit remarkable pharmacological properties. This review focuses on the recent achievements in drug discovery research associated with baicalin and baicalein for hematological malignancy therapies. The promising anticancer activities of these two flavonoids targeting diverse signaling pathways and their potential biological mechanisms in different types of hematological malignancies, as well as the combination strategy with baicalin or baicalein as chemotherapeutic adjuvants for recent therapies in these intractable diseases are discussed. Meanwhile, the biotransformation of baicalin and baicalein and the relevant approaches to improve their bioavailability are also summarized.