Lipoxygenase inhibitors from the latex of Calotropis Procera

Phytomodulatory proteins isolated from Calotropis procera latex promote glycemic control by improving hepatic mitochondrial function in HepG2 cells

The medicinal uses of Calotropis procera are diverse, yet some of them are based on effects that still lack scientific support. Control of diabetes is one of them. Recently, latex proteins from C. procera latex (LP) have been shown to promote in vivo glycemic control by the inhibition of hepatic glucose production via AMP-activated protein kinase (AMPK). Glycemic control has been attributed to an isolated fraction of LP (CpPII), which is composed of cysteine peptidases (95%) and osmotin (5%) isoforms. Those proteins are extensively characterized in terms of chemistry, biochemistry and structural aspects. Furthermore, we evaluated some aspects of the mitochondrial function and cellular mechanisms involved in CpPII activity. The effect of CpPII on glycemic control was evaluated in fasting mice by glycemic curve and glucose and pyruvate tolerance tests. HepG2 cells was treated with CpPII, and cell viability, oxygen consumption, PPAR activity, production of lactate and reactive oxygen species, mitochondrial density and protein and gene expression were analyzed. CpPII reduced fasting glycemia, improved glucose tolerance and inhibited hepatic glucose production in control animals. Additionally, CpPII increased the consumption of ATP-linked oxygen and mitochondrial uncoupling, reduced lactate concentration, increased protein expression of mitochondrial complexes I, III and V, and activity of peroxisome-proliferator-responsive elements (PPRE), reduced the presence of reactive oxygen species (ROS) and increased mitochondrial density in HepG2 cells by activation of AMPK/PPAR. Our findings strongly support the medicinal use of the plant and suggest that CpPII is a potential therapy for prevention and/or treatment of type-2 diabetes. A common epitope sequence shared among the proteases and osmotin is possibly the responsible for the beneficial effects of CpPII.

Lignans from Lepidium meyenii and Their Anti-Inflammatory Activities

Meyeniines A-C (1-3), three new lignans, two known neolignans (4-5), and three known lignans (6-8) were isolated from the rhizomes of Lepidium meyenii. Their structures were identified by comprehensive spectroscopic analyses and computational methods. Compound 1 represents a unique lignan featuring an aromatic ring migration. Compounds 2 and 4-6 were analyzed by chiral HPLC column as enantiomers. Biological evaluation revealed that compound 8 could inhibit IL-6 production in lipopolysaccharide (LPS) induced RAW264.7 cells in a dose-dependent manner.

An Overview of the Characteristics and Potential of Calotropis procera From Botanical, Ecological, and Economic Perspectives

Calotropis procera (Aiton) Dryand. (commonly known as the apple of sodom, calotrope, and giant milkweed) is an evergreen, perennial shrub of the family Apocynaceae, mainly found in arid and semi-arid regions. It is a multipurpose plant, which can be utilized for medicine, fodder, and fuel purposes, timber and fiber production, phytoremediation, and synthesis of nanoparticles. It has been widely used in traditional medicinal systems across North Africa, Middle East Asia, and South-East Asia. At present, it is being extensively explored for its potential pharmacological applications. Several reports also suggest its prospects in the food, textile, and paper industries. Besides, C. procera has also been acknowledged as an ornamental species. High pharmacological potential and socio-economic value have led to the pantropical introduction of the plant. Morpho-physiological adaptations and the ability to tolerate various abiotic stresses enabled its naturalization beyond the introduced areas. Now, it is recognized as an obnoxious environmental weed in several parts of the world. Its unnatural expansion has been witnessed in the regions of South America, the Caribbean Islands, Australia, the Hawaiian Islands, Mexico, Seychelles, and several Pacific Islands. In Australia, nearly 3.7 million hectares of drier areas, including rangelands and Savannahs, have been invaded by the plant. In this review, multiple aspects of C. procera have been discussed including its general characteristics, current and potential uses, and invasive tendencies. The objectives of this review are a) to compile the information available in the literature on C. procera, to make it accessible for future research, b) to enlist together its potential applications being investigated in different fields, and c) to acknowledge C. procera as an emerging invasive species of arid and semi-arid regions.

Syringoleosides A-H, Secoiridoids from Syringa dilatata Flowers and Their Inhibition of NO Production in LPS-Induced RAW 264.7 Cells

Repeated column chromatography of Syringa dilatata flowers, a native shrub to Korea, led to the isolation of eight new oleoside-type secoiridoids, syringoleosides A-H (1-8), as well as five known secoiridoids (9-13). The new chemical structures were identified through spectroscopic data analysis, as well as the application of chemical methods. Compounds 1, 2, 6, 7, 11, and 13 showed suppression effects on NO production in LPS-induced RAW 264.7 cells, with IC₅₀ values ranging from 32.5 ± 9.8 to 65.7 ± 11.0 μM, and no visible toxicity. The content of the major secoiridoids in S. dilatata flowers, compounds 1, 4, 5, 8, 9, 12, and 13, were determined through HPLC analysis.