Physalactone and 4ß-Hydroxywithanolide E Isolated from Physalis peruviana Inhibit LPS-Induced Expression of COX-2 and iNOS Accompanied by Abatement of Akt and STAT1.

In previous studies, withanolides isolated from Physalis peruviana were found to exhibit anti-inflammatory potential by suppressing nitrite production induced by lipopolysaccharide (LPS) treatment. Currently, we selected two of the most potent compounds, 4ß-hydroxywithanolide E (1) and physalactone (2), to examine the underlying mechanism of action. With LPS-stimulated RAW 264.7 cells in culture, the compounds inhibited the mRNA and protein expression of iNOS and COX-2. To determine which upstream signaling proteins were involved in these effects, phosphorylation levels of three mitogen-activated protein kinases (MAPKs) including ERK1/2, JNK1/2, and p38, were examined, but found unaffected. Similarly, the degradation of IκBα was not attenuated by the compounds. However, phosphorylation of Akt at the Ser-473 residue was inhibited, as was the phosphorylation of STAT1. Interestingly, the compounds also reduced the protein level of total STAT1, possibly by ubiquitin-dependent protein degradation. In sum, these results indicate the potential of 1 and 2 to mediate anti-inflammatory effects through the unexpected mechanism of inhibiting the transcription of iNOS and COX-2 via Akt- and STAT1-related signaling pathways.

Withanolides derived from Physalis peruviana (Poha) with potential anti-inflammatory activity.

Three new withanolides, physaperuvin G (1), with physaperuvins I (2), and J (3), along with seven known derivatives (4-10), were isolated from the aerial parts of Physalis peruviana. The structures of 1-3 were determined by NMR, X-ray diffraction, and mass spectrometry. Compounds 1-10 were evaluated in lipopolysaccharide (LPS)-activated murine macrophage RAW 264.7 cells. Compounds 4, 5, and 10 with potent nitric oxide inhibitory activity in LPS-activated RAW 264.7 cells, with IC50 values in the range of 0.32-7.8µM. In addition, all compounds were evaluated for potential to inhibit tumor necrosis factor-alpha (TNF-α)-activated nuclear factor-kappa B (NF-κB) activity with transfected human embryonic kidney cells 293. Compounds 4-7 inhibited TNF-α-induced NF-κB activity with IC50 values in the range of 0.04-5.6µM.

Anti-inflammatory and Quinone Reductase Inducing Compounds from Fermented Noni (Morinda citrifolia) Juice Exudates.

A new fatty acid ester disaccharide, 2-O-(ß-d-glucopyranosyl)-1-O-(2E,4Z,7Z)-deca-2,4,7-trienoyl-ß-d-glucopyranose (1), a new ascorbic acid derivative, 2-caffeoyl-3-ketohexulofuranosonic acid γ-lactone (2), and a new iridoid glycoside, 10-dimethoxyfermiloside (3), were isolated along with 13 known compounds (4-16) from fermented noni fruit juice (Morinda citrifolia). The structures of the new compounds, together with 4 and 5, were determined by 1D and 2D NMR experiments, as well as comparison with published values. Compounds 2 and 7 showed moderate inhibitory activities in a TNF-α-induced NF-κB assay, and compounds 4 and 6 exhibited considerable quinone reductase-1 (QR1) inducing effects.

The Daniel K. Inouye College of Pharmacy Scripts: Poha Berry (Physalis peruviana) with Potential Anti-inflammatory and Cancer Prevention Activities.

The Daniel K. Inouye College of Pharmacy, during a historic event in Spring 2016, graduated the first two students in the Pacific region to earn a PhD in pharmaceutical sciences at the University of Hawai'i at Hilo. The college offers PhD programs in these five disciplines: Cancer Biology, Medicinal Chemistry, Pharmaceutics, Pharmacognosy, and Pharmacology. One of the Pharmacognosy dissertations focused on plant-derived natural products with potential anti-inflammatory and cancer chemopreventive activities. Physalis peruviana (Pp) L. originated in tropical South America. It has become naturalized and is found readily on the Island of Hawai'i. The edible fruits are commonly known as cape gooseberry or poha in Hawai'i. In part of our study, three new withanolides, physaperuvin G (1), physaperuvins I-J (2-3), along with four known withanolides, namely, 4ß-hydroxywithanolide E (4), withaperuvin C (5), and physalactone (6), coagulin (7) were isolated from the aerial parts of P. peruviana. In addition, two known compounds, phyperunolide F (8), and withanolide S (9), were isolated and identified from the poha berry fruits. The structures and absolute stereochemistry of new compounds from poha were elucidated by several spectroscopy methods: Nuclear Magnetic Resonance (NMR) spectroscopy, X-ray diffraction, and mass spectrometry analyses. All isolated poha compounds (aerial parts and fruits) were evaluated for their anti-inflammatory activity with lipopolysaccharide (LPS)-activated murine macrophage RAW 264.7 cells, and tumor necrosis factor alpha (TNF-α)-activated nuclear factor-kappa B (NF-κB) with transfected human embryonic kidney cells 293. Most of the isolated natural compounds showed activity with these assays. Additional studies were performed with models of colon cancer. Specifically, 4ß-hydroxywithanolide E (4HWE) inhibited the growth of colon cancer monolayer and spheroid cultures. The compound induced cell cycle arrest at low concentrations and apoptosis at higher concentrations. These data suggest the ingestion of poha berries may have some effect on the prevalence of colon cancer. Additionally, poha isolates compounds were evaluated for their growth inhibitory effects with U251MG glioblastoma and MDA-MB-231 breast cancer cells that harbor aberrantly-active signal transducer and activation of transcription 3 (STAT3), compared to normal NIH-3T3 mouse fibroblasts. This work has led to the filing of three provisional patents with the University of Hawai'i Office of Technology Transfer and Economic Development.

Induction of cell cycle arrest and apoptosis with downregulation of Hsp90 client proteins and histone modification by 4ß-hydroxywithanolide E isolated from Physalis peruviana.

SCOPE: Physalis peruviana (Solanaceae) is used for culinary and medicinal purposes. We currently report withanolides, isolated from P. peruviana, inhibit the growth of colon cancer monolayer and spheroid cultures. A detailed mechanistic evaluation was performed with 4ß-hydroxywithanolide E (4HWE). METHODS AND RESULTS: Treatment of HT-29 cells with low concentrations of 4HWE inhibited growth while enhancing levels of p21(Waf1/Cip1) and reducing levels of several cell cycle-related proteins. Apoptosis was induced at higher concentrations. In addition, 4HWE treatment downregulated the levels of Hsp90 client proteins. Nuclear sirtuin 1 (SIRT1) was increased and histone H3 acetylated at lysine 9 was decreased. An additional consequence of SIRT1 elevation in the nucleus may be inhibition of c-Jun activity. The expression of 21 genes was altered, including downregulation of PTGS2, and this correlated with reduced protein levels of cyclooxygenase-2 (COX-2). Overall, efficacious induction of G0/G1 cell cycle arrest at low concentrations, and induction of apoptosis at higher concentrations are interesting 4HWE-mediated phenomena that are accompanied by a complex array of molecular events. CONCLUSION: Considering the worldwide prevalence of colon cancer, and the unique mode of action mediated by 4HWE, it is reasonable to investigate additional mechanistic details and the potential utility of this compound.