Rhein suppresses SHH signaling in-vivo.

<p>(A) The fluorescent images demonstrated the immunoreactivites of GLI1 (green; FITC) and SHH (red; Rhodamine) in paraffin-embedded pancreatic tissues in which nuclei were stained blue with DAPI. (B) Protein levels of GLI1 and SHH in pancreatic homogenates of the mice were visualized on immunoblots probed with anti-GLI1 and anti-SHH antibodies whereas β-ACTIN was served as the loading reference. (C) Integrated densities of the immunobands of SHH and GLI1 were measured. Readings were normalized to the internal reference β-ACTIN and expressed as fold change over control. (D) Transcripts of <i>Gli1</i> and <i>Gli2</i> were amplified by means of qPCR, normalized to the endogenous reference <i>Gapdh</i> and expressed as fold changes over the Control group. * <i>p</i>< 0.05 when comparing to the Control group whereas <i>Φ </i><i>p</i>< 0.05 when comparing to the Cerulein group.</p

Efficient Semisynthesis of (−)-Pseudoirroratin A from (−)-Flexicaulin A and Assessment of Their Antitumor Activities

Accumulating evidence indicates that natural <i>ent</i>-kaurane diterpenoids show great potential for medical treatment of different pathological conditions including cytotoxicity, antibacterial, and anti-inflammatory activity. Among a variety of diterpenoids tested, (−)-pseudoirroratin A displayed a promising antitumor property <i>in vitro</i> and <i>in vivo</i>. However, this diterpenoid could merely be isolated in a limited amount from a rare source of <i>Isodon pseudoirrorata</i>. To overcome such scanty source, we developed a novel, facile, and efficient semisynthetic strategy to prepare (−)-pseudoirroratin A from natural (−)-flexicaulin A, which can be expediently obtained from <i>I. flexicaulis</i> in a great quantity. The three-dimensional structure and the absolute configuration of our synthetic diterpenoid have been determined and confirmed with the X-ray crystallographic analysis. More importantly, we demonstrated for the first time that pseudoirroratin A exerted significant cytotoxicity against human colorectal carcinoma cells via an induction of apoptosis, as well as a remarkable suppression on tumor growth in a colon cancer xenograft mouse model

Assessment of CP in mice.

<p>(A) Changes of body weight among the 5 groups of mice in experimental period of 6 weeks. Animals were weighed every other day over the 6-week period. (B) Wet weights of pancreatic tissues were measured at the time of sacrifice. (C, D) By means of ELISA, serum levels of TNF-α and IL-1β in mice were measured at the end of the 6-week experiment and were expressed as pg/mL. * <i>p</i>< 0.05 when comparing to the Control group whereas <i>Φ </i><i>p</i>< 0.05 when comparing to the Cerulein group. (E) Activities of α-amylase in sera were expressed as mU/L and found statistically unchanged among all groups. </p

Rhein attenuates fibrotic mediators <i>in-vitro</i>.

<p>LTC-14 cells were treated with TGF-β (0, 1, 5 and 10 ng/mL) in SFM for 24 hours and harvested for mRNA extraction (A) or protein extraction (B). Transcripts of various fibrotic markers <i>Tgf-β</i>, <i>Acta2</i> and <i>Col </i><i>I-α1</i> were amplified by means of qPCR using SYBR Green reagent, normalized to the endogenous reference <i>Gapdh</i> and expressed as fold changes over SFM control. * <i>p</i>< 0.05 and ** <i>p</i>< 0.01 when comparing to the non-TGF-β-treated SFM control. Changes of FN 1 and α-SMA proteins were determined by immunoblotting analyses. β-ACTIN was served as a loading reference. (C) LTC-14 cells were treated with TNF-α (0, 1, 10 and 20 ng/mL) in SFM for 24 hours and harvested for mRNA extraction. Expression level of <i>Acta2</i> was determined after normalizing to the endogenous reference <i>Gapdh</i>. * <i>p</i>< 0.05 when comparing to the SFM control. (D) Cytotoxicity of rhein was assessed using MTT assay. LTC-14 cells were treated with rhein at a series of concentrations for 24 hours and subjected to the MTT assay. The LD₅₀ of rhein is approximately 120 μM. LTC-14 cells were pre-incubated with or without TGF-β (5 ng/mL) for 2 hours, treated with rhein (1, 10 and 100 μM) in SFM for 24 hours and harvested for mRNA extraction (E) or immunofluorescent staining (F) or protein extraction (G). By means of qPCR, expression levels of <i>Tgf-β</i>, <i>Acta2</i> and <i>Col </i><i>I-α1</i> were determined. * <i>p</i>< 0.05 when comparing to the SFM control and <i>Φ </i><i>p</i>< 0.05 when comparing to the TGF-β-treated control. Immunoreactivities of α-SMA were visualized by FITC (green) whereas nuclei were stained blue with DAPI. Magnification 400 ×. (H) LTC-14 cells were transfected with siRNA duplex targeting <i>Shh</i> (20 nM) or the non-silencing control duplex (20 μM) for 24 hours prior to the incubation of TGF-β (5 ng/mL) with or without treatment of rhein (10 μM). By means of qPCR, expression levels of <i>Acta2</i> were determined. (I) LTC-14 cells were pre-incubated with or without TGF-β (5 ng/mL) for 2 hours and treated with rhein (Rh) or curcumin (Cur) at 10 μM for 24 hours prior to mRNA extraction. By means of qPCR, expression levels of <i>Acta2</i> and <i>Col </i><i>I-α1</i> were determined. * <i>p</i>< 0.05 when comparing to the SFM control and <i>Φ </i><i>p</i>< 0.05 when comparing to the TGF-β-treated control.</p