Bergapten

Int Orthop. 2014 Mar;38(3):627-34.

Bergapten prevents lipopolysaccharide mediated osteoclast formation, bone resorption and osteoclast survival.[Pubmed: 24305787]

METHODS AND RESULTS:
To investigate the effect of Bergapten on osteoclastic bone resorption, RAW264.7 cells were treated with Bergapten for six days in the presence of LPS, and the area of bone resorption was analyzed with Image Pro-Plus. Next, we examined apoptosis of RAW264.7 cells after Bergapten incubation for 48 hours by flow cytometer using annexin V/propidium iodide (PI) double labeling. Finally, osteoclast survival was observed by Hoechst 33342 labeling and Western blotting after Bergapten treatment for 24 hours. RESULTS: Data showed that Bergapten (5-40 μmol/L) dose-dependently inhibited LPS-induced osteoclast formation and bone resorption. Treatment with Bergapten triggered apoptotic death of osteoclast precursor RAW264.7 cells in a dose-dependent manner. Furthermore, Bergapten significantly reduced the survival of mature osteoclast, as demonstrated by emergence of apoptotic nuclei and activation of apoptotic protein caspase 3/9.
CONCLUSIONS:
These findings suggest that Bergapten effectively prevents LPS-induced osteoclastogenesis, bone resorption and survival via apoptotic response of osteoclasts and their precursors. The study identifies Bergapten as an inhibitor of osteoclast formation and bone resorption and provides evidence that Bergapten might be beneficial as an alternative for prevention and treatment of inflammatory bone loss.

Nat Prod Res. 2011 Sep;25(15):1444-9.

Effect of bergapten from Heracleum nepalense root on production of proinflammatory cytokines.[Pubmed: 19662568]

In the present investigation, the anti-inflammatory activity of isolated Bergapten from hydroalcoholic extract of Heracleum nepalense root was evaluated in vitro using human peripheral blood mononuclear cells (PBMCs).
METHODS AND RESULTS:
Bergapten exhibited significant inhibition of the production of pro-inflammatory cytokines, namely tumour necrotic factor-α (TNF-α) and interleukin-6 (IL-6) by PBMCs stimulated with lipopolysaccharide in a concentration-dependent manner.

J Am Acad Dermatol. 1988 Feb;18(2 Pt 1):333-8.

5-Methoxypsoralen (Bergapten) for photochemotherapy. Bioavailability, phototoxicity, and clinical efficacy in psoriasis of a new drug preparation.[Pubmed: 3279089]

In a previous study we evaluated a microcrystalline preparation of 5-methoxypsoralen (5-MOP; Bergapten) for its photochemotherapeutic properties. Preliminary data indicated that the clinical efficacy of 5-MOP is comparable to that of 8-methoxypsoralen. 5-MOP appeared as a promising alternative photosensitizer for the management of psoriasis because of the almost complete lack of phototoxic and drug intolerance reactions that are frequently encountered in patients undergoing 8-MOP photochemotherapy.
METHODS AND RESULTS:
With a new liquid preparation of 5-MOP we have now extended our earlier investigation on a larger clinical scale and have correlated the clinical response with the bioavailability of the drug. Serum level determinations showed an absorption rate of only approximately 25% that of 8-MOP. When administered in the same dosage as 8-MOP, 5-MOP turned out to be significantly less effective; however, by doubling the oral dosage, comparable results in terms of clearing of psoriasis were obtained. Also with this high-dose 5-MOP regimen, no drug intolerance was noted and other side effects, such as severe erythema, pruritus, and nausea, occurred only rarely.
CONCLUSIONS:
We propose 5-MOP as a valuable alternative for photochemotherapy (PUVA) of PUVA-responsive diseases.

Breast Cancer Res Treat. 2012 Nov;136(2):443-55.

Bergapten induces ER depletion in breast cancer cells through SMAD4-mediated ubiquitination.[Pubmed: 23053665]

ERα function is crucial for the development of normal mammary gland as well as in the process of progression of breast cancer cells. Signals that target receptor levels contribute to regulate estrogens effects in the cells. An intricate cross-regulation has been documented between ERα and TGF-β down-stream molecules: SMAD2, SMAD3, and SMAD4, that can bind ERα and regulate their signaling. Thus, identification of natural anticancer drugs able to influence the latter molecule might provide alternative choices for breast cancer treatment. Taking into account our previous published data we wanted to study the effect of 5-Methoxypsoralen (Bergapten) on ERα and on TGF-β pathway.
METHODS AND RESULTS:
We reported that Bergapten, a coumarin containing compound, effectively depletes ERα in MCF-7 breast cancer sensitive cells and in tamoxifen-resistant clone. The decrease of ERα protein after Bergapten treatment results from the ubiquitine-proteasome pathway as demonstrated by the use of MG-132. IP experiments with ER antibody, demonstrated that the protein has physical interaction with SMAD4 and poly-ubiquitine and the amount of ubiquitinated receptor, linked to SMAD4, is greater under Bergapten. The crucial role played by SMAD4, in this process, emerges from the observation that in breast cancer cells, silencing of SMAD4, resulted in increased expression of endogenous ERα in both control and Bergapten-treated cells, compared to wild- type cells. The same results were confirmed in siRNA TGF-β RII cells.
The results suggest a novel negative regulation of ERα by TGF-β/SMAD4 in breast cancer cells and indicate that the SMAD4 protein is involved in the degradation of ERα induced by Bergapten. CONCLUSIONS:
We propose that Bergapten may efficiently act as a natural antitumoral agent, able to deplete ERα from breast cancer tamoxifen-sensitive and resistant cells, thereby retraining the effect of membrane signals targeting ERα and in such way its mitogenic potentiality.

FEBS Lett. 2010 Jun 3;584(11):2321-6.

Breast cancer cell survival signal is affected by bergapten combined with an ultraviolet irradiation.[Pubmed: 20371365]

METHODS AND RESULTS:
In this study we have reported that Bergapten (B) and Bergapten plus UV (PUVA) are able to significantly affect MCF-7, ZR-75 and SKBR-3 breast cancer cell proliferations. B induced a lowering of PI3K/AKT survival signal in MCF-7 cells even in presence of IGF-I stimulation. Furthermore, B and in a higher extent, PUVA up-regulated the p53 mRNA and the protein content. An increased co-association between p21 WAF and proliferating cell nuclear antigen (PCNA) has been observed in PUVA-treated MCF-7 cells, thus inhibiting DNA replication.
CONCLUSIONS:
These results highlight how B, and its photoactivated compound, exert antiproliferative effects and induce apoptotic responses in breast cancer cells.