Barbaloin: a concise report of its pharmacological and analytical aspects

Barbaloin is C-glucoside of aloe emodin anthrone which is found in the plant name as Aloe vera is a perennial succulent (Liliaceal), also called the healing plant. Barbaloin have variety of pharmacological activity such as strong inhibitory effect on histamine release, anti-inflammatory, cathartic, antiviral, antimicrobial, anticancer, antioxidant activity and alternative for pharmaceutical or cosmetic applications. The peak amount of barbaloin was reached about 3 h after oral administration. Concentration of barbaloin in Aloe vera leaves was shown to depend on the leaf part, age, and position of the leaf. Young leaves contain more barbaloin compared to old one. Various researches have been done on barbaloin but still the relationship between the barbaloin and its overall effect has not been clarified. A more specific perceptive of the pharmacological activities of barbaloin is required to develop for pharmaceutical purpose. Many attempts have been made regarding its isolation, biological activity to examine their effects, and clarify their functional mechanism. This review gives a brief idea about its uses, ethnomedicinally and commercially important analytical techniques and their pharmacological activities.

Mucoadhesive Polymeric Films to Enhance Barbaloin Penetration Into Buccal Mucosa: a Novel Approach to Chemoprevention

Nowadays, chemoprevention by administering natural supplements is considered an attractive strategy to reverse, suppress, or prevent the evolution of premalignant oral lesions. In particular, Barbaloin exhibits anti-proliferative, anti-inflammatory, and anti-cancer properties, and it results useful in multi-therapy with classic chemotherapeutics. Therefore, in this work, mucoadhesive buccal films, as locoregional drug delivery system able to provide a targeted and efficient therapeutic delivery of Barbaloin, are proposed. Thus, Aloin extract-loaded Eudragit® RL100 or Eudragit® RS100-based buccal films were designed in order to obtain an easily self-administrable formulation capable of promoting Barbaloin penetration into buccal mucosa and assuring high patient compliance. Large amounts of extract (44%) were loaded into the polymer matrix and six formulations were prepared varying polymers and plasticizers ratios. For all formulations, physical form (thermogravimetric analysis-differential scanning calorimetry, TGA-DSC), swelling degree, mucoadhesiveness, drug release, and ability to promote drug penetration in mucosa have been investigated. After a sequential selection process, Eudragit RS 100-based film, with low PVP and high plasticizers amounts, emerged as the most promising. It results appropriately flexible, uniform in terms of weight, thickness and drug content, as well as characterized by suitable surface pH, good mucoadhesiveness, and low swelling degree. It displays a Higuchian drug release behavior up to 89% of Barbaloin released, thus demonstrating that diffusion through the matrix is the main release mechanism. Remarkable penetration enhancer properties of film were demonstrated by evidence of Barbaloin accumulation into buccal mucosa up to 10-fold higher than those obtained following administration of Aloin solution.

Barbaloin loaded polydopamine-polylactide-TPGS (PLA-TPGS) nanoparticles against gastric cancer as a targeted drug delivery system: Studies in vitro and in vivo

Gastric cancer is the third leading cause of cancer-associated death worldwide. Although a decrease in its incidence is observed, gastric cancer still poses a major clinical challenge due to poor prognosis and limited treatments. Barbaloin (BBL) is a main medicinal composition of the Chinese traditional medicine aloe vera. BBL has various bioactivities, including anti-oxidant, anti-inflammatory and anti-tumor properties. Polydopamine (pD)-based surface modification is easy to functionalize polymeric nanoparticles (NPs) surfaces with ligands and/or additional polymeric layers. In the present study, BBL-loaded formulations was developed with pD-modified NPs, which was synthesized by polylactide-TPGS (PLA-TPGS) (pD-PLA-TPGS/NPs). And galactosamine (Gal) was conjugated on the prepared NPs (Gal-pD-PLA-TPGS/NPs) for targeting the gastric cancer cells. Here, we found that BBL-loaded Gal-pD-PLA-TPGS/NPs showed the highest cellular uptake efficacy in gastric cancer cells. Gal-pD-PLA-TPGS/NPs more significantly reduced the gastric cancer cell viability. Further, greater apoptosis, autophagy and ROS generation was induced by Gal-pD-PLA-TPGS/NPs in gastric cancer cells. Additionally, compared to the other two NPs, Gal-pD-PLA-TPGS/NPs most markedly decreased ATP levels in gastric cancer cells. In vivo, Gal-pD-PLA-TPGS/NPs were specifically targeted to tumor site. Moreover, Gal-pD-PLA-TPGS/NPs exhibited the most anti-tumor effects, as evidenced by the lowest tumor volume and tumor weight. Of note, there was no significant difference was observed in body and liver weight, as well as the histological changes in major organs isolated from each group of mice. Together, the findings indicated that BBL-loaded Gal-pD-PLA-TPGS/NPs could be targeted to gastric cancer cells to suppress tumor progression without toxicity.

Barbaloin: an amazing chemical from the 'wonder plant' with multidimensional pharmacological attributes

Aloe vera (L.) Burm.f. is nicknamed the 'Miracle plant' or sometimes as the 'Wonder plant'. It is a plant that has been used since ancient times for the innumerable health benefits associated with it. It is one of the important plants that has its use in conventional medicinal treatments. It is a perennial succulent, drought-tolerant member of the family Asphodelaceae. There are scores of properties associated with the plant that help in curing various forms of human ailments. Extracts and gels obtained from plants have been shown to be wonderful healers of different conditions, mainly various skin problems. Also, this plant is popular in the cosmetics industry. The underlying properties of the plant are now mainly associated with the natural phytochemicals present in the plant. Diverse groups of phytoingredients are found in the plant, including various phenolics, amino acids, sugars, vitamins, and different other organic compounds, too. One of the primary ingredients found in the plant is the aloin molecule. It is an anthraquinone derivative and exists as an isomer of Aloin A and Aloin B. Barbaloin belonging to the first group is a glucoside of the aloe-emodin anthrone molecule. Various types of pharmacological properties exhibited by the plant can be attributed to this chemical. Few significant ones are antioxidant, anti-inflammatory, anti-diabetic, anti-cancer, anti-microbial, and anti-viral, along with their different immunity-boosting actions. Recently, molecular coupling studies have also found the role of these molecules as a potential cure against the ongoing COVID-19 disease. This study comprehensively focuses on the numerous pharmacological actions of the primary compound barbaloin obtained from the Aloe vera plant along with the mechanism of action and the potent application of these natural molecules under various conditions.

Spectroscopic characterization of different protonation/deprotonation states of Barbaloin in aqueous solution

Barbaloin (10-glucopyranosyl-1,8-dihydroxy-3-(hydroxymethyl)-9(10H)-anthraquinone: aloin A), present in Aloe species, is widely used in food, cosmetic and pharmaceutical industries. Here we characterize its optical absorption and emission spectra in aqueous solution at different pH values. Through pH titration, using both absorption and fluorescence spectroscopy, two pK_a values for Barbaloin were determined: pK_a1=9.6±0.6 and pK_a2=12.6±0.8. These acidity constants were found to be higher than those found for Emodin, a similar molecule which lacks the sugar moiety present in Barbaloin. Performing quantum mechanical calculations for non-ionized, singly, doubly, and triply deprotonated forms of Barbaloin in vacuum and in water, we assigned the positions of the site for the first and third deprotonation in the anthraquinone group, and the second deprotonation in the glucose group. The instability of Barbaloin in high pH solutions is discussed here, and the optical absorption and fluorescence spectra due to products resulted from Barbaloin degradation at high pH is well separated from the Barbaloin original spectra. Biological fluids have specific pH values to maintain homeostasis, hence determining the pK_a of Barbaloin is important to evaluate the mechanism of action of this drug in different parts of an organism as well as to predict pharmacological relevant parameters, such as absorption, distribution, metabolism, and excretion.

Barbaloin Promotes Osteogenic Differentiation of Human Bone Marrow Mesenchymal Stem Cells: Involvement of Wnt/β-catenin Signaling Pathway

BACKGROUND

Barbaloin, found in Aloe vera, exerts broad pharmacological activities, including antioxidant, anti-inflammatory, and anti-cancer. This study aims to investigate the effects of barbaloin on the osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs).

METHODS

Osteogenic induction of hBMSCs was performed in the presence or absence of barbaloin. Cell viability was determined by using the CCK-8 assay. The characteristic of hBMSCs was identified by using flow cytometry. Intracellular alkaline phosphatase (ALP) staining was performed to evaluate the ALP activity in hBMSCs. Alizarin Red S staining was performed to evaluate the matrix mineralization. The mRNA and protein levels of target genes were determined using qRT-PCR and western blotting, respectively.

RESULTS

Treatment with barbaloin (10 and 20 μg/mL) significantly increased cell viability of hBMSCs after 72 hours. In addition, treatment with barbaloin increased the mRNA expression levels of ALP and its activities. Treatment with barbaloin also increased matrix mineralization and the mRNA and protein levels of late-differentiated osteoblast marker genes BMP2, RUNX2, and SP7 in hBMSCs. The underlying mechanisms revealed that barbaloin increased the protein expressions of Wnt/β-catenin pathway-related biomarkers.

CONCLUSION

Barbaloin promotes osteogenic differentiation of hBMSCs by the regulation of the Wnt/β-catenin signaling pathway.