Betulinic acid

Toxicol Appl Pharmacol. 2014 Mar 1;275(2):152-62.

Betulinic acid, a bioactive pentacyclic triterpenoid, inhibits skeletal-related events induced by breast cancer bone metastases and treatment.[Pubmed: 24463094]

The present study provides evidence on the protective and therapeutic potential of Betulinic acid on cancer-associated bone diseases. Betulinic acid is a naturally occurring triterpenoid with the beneficial activity to limit the progression and severity of cancer, diabetes, cardiovascular diseases, atherosclerosis, and obesity.
METHODS AND RESULTS:
We first investigated its effect on breast cancer cells, osteoblastic cells, and osteoclasts in the vicious cycle of osteolytic bone metastasis. Betulinic acid reduced cell viability and the production of parathyroid hormone-related protein (PTHrP), a major osteolytic factor, in MDA-MB-231 human metastatic breast cancer cells stimulated with or without tumor growth factor-β. Betulinic acid blocked an increase in the receptor activator of nuclear factor-kappa B ligand (RANKL)/osteoprotegerin ratio by downregulating RANKL protein expression in PTHrP-treated human osteoblastic cells. In addition, Betulinic acid inhibited RANKL-induced osteoclastogenesis in murine bone marrow macrophages and decreased the production of resorbed area in plates with a bone biomimetic synthetic surface by suppressing the secretion of matrix metalloproteinase (MMP)-2, MMP-9, and cathepsin K in RANKL-induced osteoclasts. Furthermore, oral administration of Betulinic acid inhibited bone loss in mice intra-tibially inoculated with breast cancer cells and in ovariectomized mice causing estrogen deprivation, as supported by the restored bone morphometric parameters and serum bone turnover markers.
CONCLUSIONS:
Taken together, these findings suggest that Betulinic acid may have the potential to prevent bone loss in patients with bone metastases and cancer treatment-induced estrogen deficiency.

Appl Microbiol Biotechnol. 2014 Apr;98(7):3081-9.

Increase of betulinic acid production in Saccharomyces cerevisiae by balancing fatty acids and betulinic acid forming pathways.[Pubmed: 24389702]

Betulinic acid is a plant-based triterpenoid that has been recognized for its antitumor and anti-HIV activities. The level of Betulinic acid in its natural hosts is extremely low.
METHODS AND RESULTS:
In the present study, we constructed Betulinic acid biosynthetic pathway in Saccharomyces cerevisiae by metabolic engineering. Given the Betulinic acid forming pathways sharing the common substrate acetyl-CoA with fatty acid synthesis, the metabolic fluxes between the two pathways were varied by changing gene expressions, and their effects on Betulinic acid production were investigated. We constructed nine S. cerevisiae strains representing nine combinations of the flux distributions between Betulinic acid and fatty acid pathways. Our results demonstrated that it was possible to improve the Betulinic acid production in S. cerevisiae while keeping a desirable growth phenotype by optimally balancing the carbon fluxes of the two pathways. Through modulating the expressions of the key genes on Betulinic acid and fatty acid pathways, the difference in Betulinic acid yield varied largely in the range of 0.01-1.92 mg L(-1) OD(-1).
CONCLUSIONS:
The metabolic engineering approach used in this study could be extended for synthesizing other triterpenoids in S. cerevisiae.

Ultrastruct Pathol . Jan-Feb 2018;42(1):49-54.

Betulinic acid induces apoptosis and ultrastructural changes in MDA-MB-231 breast cancer cells[Pubmed: 29192840]

Abstract The aim of this study is to investigate the effects of Betulinic acid (BA) on triple-negative breast cancer MDA-MB-231 cells and observe the ultrastructural changes. The concentration of BA required to induce apoptosis in MDA-MB-231 cells has been previously reported. In this study, a cell counting kit-8 proliferation assay was used to measure cell viability and the apoptosis rate. Western blotting was performed to observe the protein expression levels of Bcl-2. Cell morphology and changes in cell density were observed by microscopy. Electron microscopy revealed pyknotic nuclei as well as vacuoles. Collectively, our results showed the morphological mechanisms by which BA impairs the ultrastructure of MDA-MB-231 cells.

Naunyn Schmiedebergs Arch Pharmacol . 2018 Mar;391(3):285-297.

Betulinic acid alleviates dextran sulfate sodium-induced colitis and visceral pain in mice[Pubmed: 29279966]

Abstract Betulinic acid (BA) exhibits many biological effects including anti-inflammatory and anti-oxidant activities. Free radicals and pro-inflammatory mediators play an important role in the pathology of inflammatory bowel disease (IBD) and associated pain. We, therefore, examined the anti-oxidant, anti-inflammatory, and anti-nociceptive potential of BA in colitis. Colitis was induced with 3% (w/v) dextran sulfate sodium (DSS) in drinking water in mice for 1to7 days. BA (3, 10 and 30 mg/kg) was given orally for 0 to 7 days. BA was also tested for its efficacy in acetic acid and mustard oil-induced visceral nociception in mice at same doses. BA significantly prevented diarrhea; bleeding and colonic pathological changes induced by DSS. Further, BA reduced the colon nitrite, malondialdehyde, myeloperoxidase, and lipid hydroperoxide levels and restored the superoxide dismutase, catalase and reduced glutathione levels to normalize the redox balance in DSS-exposed mice. Inflammatory mediators like matrix metalloproteinase-9 and prostaglandin E2 levels were also significantly attenuated by BA in colitis mice. Additionally, BA reduced acetic acid and mustard oil-induced visceral pain in mice. In conclusion, the results of the present study suggest that BA possesses good anti-nociceptive activity and the anti-IBD effects of BA are due to its anti-oxidant and anti-inflammatory potential.

Food Chem Toxicol. 2014 Jun;68:38-43.

Betulinic acid isolated from Vitis amurensis root inhibits 3-isobutyl-1-methylxanthine induced melanogenesis via the regulation of MEK/ERK and PI3K/Akt pathways in B16F10 cells.[Pubmed: 24632067]

Previously, Betulinic acid was identified as one of the main compounds responsible for the anti-melanogenic effect in Vitis amurensis root.
METHODS AND RESULTS:
In this study, we investigated the precise mechanism underlying the anti-melanogenic activity of Betulinic acid in B16F10 cells. Betulinic acid significantly attenuated 3-isobutyl-1-methylxanthine (IBMX)-induced melanin production by inhibiting tyrosinase, tyrosinase related protein (TRP)-1, and TRP-2 expression through the modulation of their corresponding transcription factors, microphthalamia associated transcription factor (MITF) and cAMP response element binding protein (CREB), in B16F10 cells. In addition, phosphorylation of mitogen-activated protein kinase kinase (MEK)/extracellular regulated kinase (ERK) and phosphoinositide 3-kinase (PI3K)/Akt, involved in the melanogenic processes, were ameliorated by Betulinic acid treatment. Role of MEK/ERK and PI3K/Akt signaling pathway in the melanogenesis was confirmed by using specific inhibitors, PD98059 (for MEK/ERK) and LY294002 (for PI3K/Akt), respectively. As a result, Betulinic acid inhibited melanin production by tyrosinase, TRP-1, and TRP-2 inhibition through the regulation of CREB and MITF, which was accompanied with MEK/ERK and PI3K/Akt inactivation in IBMX-stimulated B16F10 cells.
CONCLUSIONS:
Consequently, these results demonstrate a novel molecular function of Betulinic acid derived from V. amurensis root in melanogenesis, which in turn enhances our understanding on the application of cosmetic therapy for reducing skin hyperpigmentation.

J Immunol. 2003 Sep 15;171(6):3278-86.

Betulinic acid suppresses carcinogen-induced NF-kappa B activation through inhibition of I kappa B alpha kinase and p65 phosphorylation: abrogation of cyclooxygenase-2 and matrix metalloprotease-9.[Pubmed: 12960358]

Betulinic acid (BA), a pentacyclic triterpene isolated from the bark of the white birch tree, has been reported to be a selective inducer of apoptosis in tumor cells. It also exhibits anti-inflammatory and immunomodulatory properties. How BA mediates these effects is not known. Because of the critical role of the transcription factor NF-kappaB in growth modulatory, inflammatory, and immune responses, we postulated that BA modulates the activity of this factor.
METHODS AND RESULTS:
In this study we investigated the effect of BA on NF-kappaB and NF-kappaB-regulated gene expression activated by a variety of inflammatory and carcinogenic agents. BA suppressed NF-kappaB activation induced by TNF, PMA, cigarette smoke, okadaic acid, IL-1, and H(2)O(2). The suppression of NF-kappaB activation was not cell-type specific. BA suppressed the activation of IkappaBalpha kinase, thus abrogating the phosphorylation and degradation of IkappaBalpha. We found that BA inhibited NF-kappaB activated by TNFR 1, TNFR-associated death domain, TNFR-associated factor 2, NF-kappaB-inducing kinase, and IkappaBalpha kinase. Treatment of cells with this triterpinoid also suppressed NF-kappaB-dependent reporter gene expression and the production of NF-kappaB-regulated gene products such as cyclooxygenase-2 and matrix metaloproteinase-9 induced by inflammatory stimuli. Furthermore, BA enhanced TNF-induced apoptosis.
CONCLUSIONS:
Overall, our results indicated that BA inhibits activation of NF-kappaB and NF-kappaB-regulated gene expression induced by carcinogens and inflammatory stimuli. This may provide a molecular basis for the ability of BA to mediate apoptosis, suppress inflammation, and modulate the immune response.

Zhongguo Zhong Yao Za Zhi. 2014 Mar;39(6):1097-100.

Research on HBV DNA inhibition of plasmid acute infection mouse with betulinic acid[Pubmed: 24956858]

Betulinic acid is a naturally occurring pentacyclic triterpenoid, which has antiretroviral, antimalarial, and anti-inflammatory properties. The purpose of this study is to investigate the HBV DNA replication inhibition in the mouse model with Betulinic acid.
METHODS AND RESULTS:
Hydrodynamic injection method via the tail vein with the Paywl. 3 plasmid was used to establish the animal mode (n = 15), and the mice were randomly divided into the PBS control group (n = 5), Betulinic acid treatment group (n = 5) and lamivudine control group (n = 5). The day after successful modeling , the mice would have taken Betulinic acid (100 mg x kg(-1)), lamivudine (50 mg x kg(-1)), PBS drugs orally, once daily for 7 days, blood samples were acquired from the orbital venous blood at 3, 5, 7 days after the administering, HBsAg and HBeAg in serum concentration were measured by ELISA and the mice were sacrificed after 7 days, HBV DNA southern detections were used with part of mice livers. The results showed that Betulinic acid significantly inhibited the expression of HbsAg in the mice model at the fifth day compared with the control group, and there was no significant differences between the effects of lamivudine and the PBS control group; both the Betulinic acid and lamivudine groups had no significant inhibition for the HBeAg expression; the HBV DNA expressions of the liver tissue from the Betulinic acid and lamivudine groups were inhibited compared with the control group.
CONCLUSIONS:
Taken together, these results reveal Betulinic acid can inhibit the HBsAg expression and replication of the liver HBV DNA in the mouse model.