Gellan gum-based hydrogel containing nanocapsules for vaginal indole-3-carbinol delivery in trichomoniasis treatment

Trichomonas vaginalis infection is the STI most common worldwide. Indole-3-carbinol (I3C) is a phytochemical presenting promising biological activities. In this study, design, formulation, and evaluation of a vaginal hydrogel containing I3C-loaded nanocapsules for the treatment of trichomoniasis have been investigated. Nanocapsules of Eudragit® RS100 and rosehip oil containing I3C (NC-I3C) were prepared by interfacial deposition of preformed polymer method. In vitro evaluations showed that free I3C (IC50 = 3.36 µg/mL) was able to reduce the trophozoites viability at higher concentrations (3.13 and 6.25 µg/mL), while nanoencapsulation (IC50 = 2.09 µg/mL) reduced the viability at all concentrations evaluated. Comparing free and nanoencapsulated I3C, we observe that nanoencapsulation improved anti-T. vaginalis activity. In order to obtain a formulation for vaginal administration, hydrogels (HG-NC-I3C) were prepared by thickening the NC-I3C with gellan gum. HG-NC-I3C presented particle size below 195 nm, low polydispersity index (<0.2), I3C content = 0.50 ± 0.01 mg/g, pH = 7.05, non-Newtonian pseudoplastic flow behavior and exhibited mucoadhesion to cow's vaginal mucosa. Evaluation of irritation potential by chorioallantoic membrane method indicated that the formulations are considered non-irritating. Besides that, permeation through the cow's vaginal mucosa showed that nanoencapsulation promoted I3C controlled release. This way, the developed HG-NC-I3C can be considered a promising approach for trichomoniasis treatment through vaginal administration.

Discovery of 2,3'-diindolylmethanes as a novel class of PCSK9 modulators

Proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes the degradation of low density lipoprotein receptor (LDLR). Anti-PCSK9 agents have been approved for the treatment of hypercholesterolemia. We recently discovered a series of small-molecule PCSK9 modulators that contains a relatively small pharmacophore of 2,3'-diindolylmethane with molecular weights around only 250. These molecules can significantly lower the amount of PCSK9 protein in a cell-based phenotypic assay. Our SAR studies yielded compound 16 with a IC₅₀-value of 200 nM. No obvious cytotoxicity was observed at concentrations below 50 µM.

Anticancer properties of a new non-oxido vanadium(IV) complex with a catechol-modified 3,3'-diindolylmethane ligand

In order to identify new active drug candidates against cancer diseases we investigated the tumor cell growth inhibition, formation of reactive oxygen species, mitochondrial membrane damage, cell cycle arrest and DNA binding activity of a new bis(triethylammonium) tris[1,1-bis(indol-3-yl)-1-(3,4-catecholate)methane]vanadate(IV) complex. It exhibited significant antiproliferative activity against various cancer cell lines, showed a stronger DNA binding than cisplatin and led to mitochondrial damage, a formation of reactive oxygen species, and a cell cycle arrest in the G2/M phase of cancer cells.

Autophagy inhibition improves the chemotherapeutic efficacy of cruciferous vegetable-derived diindolymethane in a murine prostate cancer xenograft model

Prostate cancer is the second leading cause of cancer-related deaths in men in North America and there is an urgent need for development of more effective therapeutic treatments against this disease. We have recently shown that diindolylmethane (DIM) and several of its halogenated derivatives (ring-DIMs) induce death and protective autophagy in human prostate cancer cells. However, the in vivo efficacy of ring-DIMs and the use of autophagy inhibitors as adjuvant therapy have not yet been studied in vivo. The objective of this study was to determine these effects on tumor growth in nude CD-1 mice bearing bioluminescent androgen-independent PC-3 human prostate cancer cells. We found that chloroquine (CQ) significantly sensitized PC-3 cells to death in the presence of sub-toxic concentrations of DIM or 4,4'-Br₂DIM in vitro. Moreover, a combination of DIM (10 mg/kg) and CQ (60 mg/kg), 3× per week, significantly decreased PC-3 tumor growth in vivo after 3 and 4 weeks of treatment. Furthermore, 4,4'-Br₂DIM at 10 mg/kg (3× per week) significantly inhibited tumour growth after 4 weeks of treatment. Tissues microarray analysis showed that DIM alone or combined with CQ induced apoptosis marker TUNEL; the combination also significantly inhibited the cell proliferation marker Ki67. In conclusion, we have confirmed that DIM and 4,4'-Br₂DIM are effective agents against prostate cancer in vivo and shown that inhibition of autophagy with CQ enhances the anticancer efficacy of DIM. Our results suggest that including selective autophagy inhibitors as adjuvants may improve the efficacy of existing and novel drug therapies against prostate cancer.

A randomized, placebo-controlled trial of diindolylmethane for breast cancer biomarker modulation in patients taking tamoxifen

PURPOSE

Diindolylmethane (DIM), a bioactive metabolite of indole-3-carbinol found in cruciferous vegetables, has proposed cancer chemoprevention activity in the breast. There is limited evidence of clinically relevant activity of DIM or long-term safety data of its regular use. A randomized, double-blind, placebo-controlled trial was conducted to determine the activity and safety of combined use of BioResponse DIM® (BR-DIM) with tamoxifen.

METHODS

Women prescribed tamoxifen (n = 130) were randomly assigned oral BR-DIM at 150 mg twice daily or placebo, for 12 months. The primary study endpoint was change in urinary 2/16α-hydroxyestrone (2/16α-OHE1) ratio. Changes in 4-hydroxyestrone (4-OHE1), serum estrogens, sex hormone-binding globulin (SHBG), breast density, and tamoxifen metabolites were assessed.

RESULTS

Ninety-eight women (51 placebo, 47 DIM) completed intervention; compliance with treatment was >91%. BR-DIM increased the 2/16α-OHE1 ratio (+3.2 [0.8, 8.4]) compared to placebo (-0.7 [-1.7, 0.8], P < 0.001). Serum SHBG increased with BR-DIM compared to placebo (+25 ± 22 and +1.1 ± 19 nmol/L, respectively). No change in breast density measured by mammography or by MRI was observed. Plasma tamoxifen metabolites (endoxifen, 4-OH tamoxifen, and N-desmethyl-tamoxifen) were reduced in women receiving BR-DIM versus placebo (P < 0.001). Minimal adverse events were reported and did not differ by treatment arm.

CONCLUSION

In patients taking tamoxifen for breast cancer, daily BR-DIM promoted favorable changes in estrogen metabolism and circulating levels of SHBG. Further research is warranted to determine whether BR-DIM associated decreases in tamoxifen metabolites, including effects on endoxifen levels, attenuates the clinical benefit of tamoxifen.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01391689.

Novel diindolylmethane derivatives based NLC formulations to improve the oral bioavailability and anticancer effects in triple negative breast cancer

The present study demonstrates the promising anticancer effects of novel C-substituted diindolylmethane (DIM) derivatives DIM-10 and DIM-14 in aggressive TNBC models. In vitro studies demonstrated that these compounds possess strong anticancer effects. Caco-2 permeability studies resulted in poor permeability and poor oral bioavailability was demonstrated by pharmacokinetic studies. Nano structured lipid carrier (NLC) formulations were prepared to increase the clinical acceptance of these compounds. Significant increase in oral bioavailability was observed with NLC formulations. Compared to DIM-10, DIM-10 NLC formulation showed increase in C_max and AUC values by 4.73 and 11.19-folds, respectively. Similar pattern of increase was observed with DIM-14 NLC formulations. In dogs DIM-10 NLC formulations showed an increase of 2.65 and 2.94-fold in C_max and AUC, respectively. The anticancer studies in MDA-MB-231 orthotopic TNBC models demonstrated significant reduction in tumor volumes in DIM-10 and DIM-14 NLC treated animals. Our studies suggest that NLC formulation of both DIM-10 and 14 is effective in TNBC models.

Diindolylmethane and Lupeol Modulates Apoptosis and Cell Proliferation in N-Butyl-N-(4-Hydroxybutyl) Nitrosamine Initiated and Dimethylarsinic Acid Promoted rat Bladder Carcinogenesis

Bladder cancer has been shown to resist programmed cell death with altered expression of both pro-apoptotic and anti-apoptotic proteins. To study is to investigate the apoptotic properties of Diindolylmethane (DIM) and Lupeol on N-Butyl-N-(4-hydroxybutyl) Nitrosamine (BBN) initiated and Dimethylarsinic Acid (DMA) promoted urinary bladder cancer. Sixty male Wistar rats were divided into 6 groups. Group I: Control. Group II: Rats were experimentally developed bladder carcinogenesis with BBN and DMA. Group III and IV: DIM and lupeol were administered after BBN treatment for 28 weeks. Group V and VI: DIM and lupeol alone treatment for 36 weeks. All the experimental rats were maintained and euthanized after 36 weeks protocol. Urinary bladder tissues were collected and processed for further investigations. Apoptotis and cell proliferative marker such as Bax, Bcl-2, caspase-3, caspase-9 and PCNA were quantified using immunohistochemical analysis. The Immunohistochemical expression of Bax, Bcl-2, caspase-3, caspase-9 and PCNA were aberrant in BBN + DMA treated tumor group. Administration of DIM and lupeol inhibited the progression of bladder cancer, induced the expression of apoptotic Bax, caspase-3, caspase-9 and inhibited the expression of anti-apoptotic Bcl-2, PCNA in the urinary bladder of rats. Administration of diindolylmethane and lupeol treatment induces apoptosis and cellular proliferation by its anti-carcinogenic properties. From our results DIM and lupeol would be the agent or adjunct for the treatment of bladder carcinogenesis.

Double-blind randomized placebo-controlled multicenter clinical trial (phase IIa) on diindolylmethane's efficacy and safety in the treatment of CIN: implications for cervical cancer prevention

Background

The article presents the results of a clinical trial on the efficacy and safety of a novel pharmaceutical composition in the form of vaginal suppositories containing diindolylmethane in the course of cervical intraepithelial neoplasia (CIN) I–II conservative treatment. It offers an attractive drug therapy for more personalized prevention of cervical cancer.

Methods

A total of 78 women of reproductive age were included. This was a multicenter, randomized, placebo-controlled, double-blind, parallel-group trial with efficacy determined by histological evaluation of cervical biopsies. The efficacy of active drug treatment (100 and 200 mg/day) in both treatment groups was significantly higher in comparison with the placebo group, according to the primary efficacy end point (proportion of patients with complete CIN regression after 90–180 days of the study drug treatment).

Results

The efficacies were 100.0 % (confidence interval (CI) 95 %: 82.35–100.00 %), 90.5 % (CI 95 %: 69.62–98.83 %), and 61.1 % (CI 95 %: 35.75–82.70 %), for the high dose, low does, and placebo, respectively. Adverse events in the placebo group were reported in 22 % of patients (CI 95 %: 7.5–43.7 %); in the first treatment group (100 mg/day), adverse events were reported in 40.0 % of patients (CI 95 %: 21.1–61.3 %); in the second treatment group (200 mg/day), adverse events were reported in 42.0 % of patients (CI 95 %: 22.1–63.4 %). The differences in side effects between treatment groups treated with the active drug and placebo were statistically significant. No serious adverse events were reported in any of the groups.

Conclusions

Thus, the use of diindolylmethane in the form of intravaginal suppositories can be effective in patients with CIN I–II and is not accompanied by clinically significant side effects. This approach could be a better option for young women with CIN I–II as it takes in attention their reproductive plans.

Trial registration

ID: ChiCTR-INR-15007497 (2 December 2015)

Diindolylmethane, a naturally occurring compound, induces CYP3A4 and MDR1 gene expression by activating human PXR

Activation of human pregnane X receptor (hPXR)-regulated expression of cytochrome P450 3A4 (CYP3A4) and multidrug resistance protein 1 (MDR1) plays an important role in mediating adverse drug interactions. Given the common use of natural products as part of adjunct human health behavior, there is a growing concern about natural products for their potential to induce undesired drug interactions through the activation of hPXR-regulated CYP3A4 and MDR1. Here, we studied whether 3,3'-diindolylmethane (DIM), a natural health supplement, could induce hPXR-mediated regulation of CYP3A4 and MDR1 in human hepatocytes and intestinal cells. DIM, at its physiologically relevant concentrations, not only induced hPXR transactivation of CYP3A4 promoter activity but also induced gene expression of CYP3A4 and MDR1. DIM decreased intracellular accumulation of MDR1 substrate rhodamine 123, suggesting that DIM induces the functional expression of MDR1. Pharmacologic inhibition or genetic knockdown of hPXR resulted in attenuation of DIM induced CYP3A4 and MDR1 gene expression, suggesting that DIM induces CYP3A4 and MDR1 in an hPXR-dependent manner. Together, these results support our conclusion that DIM induces hPXR-regulated CYP3A4 and MDR1 gene expression. The inductive effects of DIM on CYP3A4 and MDR1 expression caution the use of DIM in conjunction with other medications metabolized and transported via CYP3A4 and MDR1, respectively.

Synthesis and biological evaluation of 2,3'-diindolylmethanes as agonists of aryl hydrocarbon receptor

Recent studies suggest that arylhydrocarbon receptor (AhR) may be a target for a number of diseases. Natural product malassezin is a AhR agonist with an interesting 2,3'-diindolylmethane skeleton. We have prepared a series of analogues of natural product malassezin using our recently developed method and tested the activity of these analogues against AhR in a cell-based assay. We found that a methyl substituent at 1'-N can significantly increase the activity and the 2-formyl group is not critical for some diindolylmethanes.