Alpinia japonica extract induces apoptosis of hepatocellular carcinoma cells through G0/G1 cell cycle arrest and activation of JNK.

Hepatic cancer was the third most prevalent cause of cancer-related death worldwide in 2018, and its incidence is increasing. While therapeutic agents for hepatic cancer have improved, these agents can cause serious side effects, including damage to healthy tissues. To overcome this limitation, more than 3,000 plants have been used globally as common alternatives for cancer treatment. The anti-cancer activity of Alpinia japonica, one of the traditional herbal medicines (Korean name: Kkot-yang-ha), was investigated. Water extract of A. japonica (AJ) decreased the cell viability of hepatic cancer cells. AJ extract showed greater than 70% loss of mitochondrial potential in HepG2 cells as demonstrated by JC-1 staining. Apoptosis was induced by treatment with AJ extract as shown through FACS analysis, and G0/G1 phase arrest of 76.66% HepG2 cells was confirmed through cell cycle analysis and quantitative RT-PCR. Improper regulation of ERK1/2 might contribute to cell death, and JNK activation is necessary for apoptosis induced by stress stimuli. AJ extract stimulated the phosphorylation of JNK and ERK1/2, mitogen-activated protein kinases (MAPKs), in HepG2 cells. AJ extract has anticancer activity by inhibiting cell cycle progression, leading to apoptosis of hepatic cancer cells. This extract could potentially be used as a therapeutic agent for hepatic cancer.

Anti-Candida Potential of Sclareol in Inhibiting Growth, Biofilm Formation, and Yeast-Hyphal Transition.

Even though Candida albicans commonly colonizes on most mucosal surfaces including the vaginal and gastrointestinal tract, it can cause candidiasis as an opportunistic infectious fungus. The emergence of resistant Candida strains and the toxicity of anti-fungal agents have encouraged the development of new classes of potential anti-fungal agents. Sclareol, a labdane-type diterpene, showed anti-Candida activity with a minimum inhibitory concentration of 50 µg/mL in 24 h based on a microdilution anti-fungal susceptibility test. Cell membrane permeability with propidium iodide staining and mitochondrial membrane potential with JC-1 staining were increased in C. albicans by treatment of sclareol. Sclareol also suppressed the hyphal formation of C. albicans in both liquid and solid media, and reduced biofilm formation. Taken together, sclareol induces an apoptosis-like cell death against Candida spp. and suppressed biofilm and hyphal formation in C. albicans. Sclareol is of high interest as a novel anti-fungal agent and anti-virulence factor.

Trichosanthes kirilowii Extract Promotes Wound Healing through the Phosphorylation of ERK1/2 in Keratinocytes.

The proliferation of keratinocytes is one of the important steps in the wound-healing process, which is regulated by various signals. Prior studies have shown that Trichosanthes kirilowii extract has the ability to promote angiogenesis. Therefore, in this study, we tested the wound-healing efficacy of Trichosanthes kirilowii extract with respect to promoting keratinocyte proliferation. A total of 100 µg/mL of Trichosanthes kirilowii extract treatment improved 145.38% of keratinocyte proliferation compared with DMSO-treated control in an MTT assay and increased 238.2% of wound closure by re-epithelialization in an in vitro wound-healing assay. Trichosanthes kirilowii extract promoted ERK1/2 phosphorylation in western blot analysis and induced the expression of the c-fos and c-jun (AP-1 transcription factors), cyclins (cell cycle regulator), and growth factors CTGF and VEGF (stimulator of angiogenesis) in qRT-PCR analysis. An in vivo wound-healing assay showed that Trichosanthes kirilowii extract improved wound healing, and the significant difference in wound closure compared with DMSO-treated control was shown on days 6 and 7 with a mouse model. Taken together, we demonstrate that Trichosanthes kirilowii extract promotes the proliferation of keratinocytes by activating ERK1/2 and increasing the mRNA expression of c-fos, c-jun, CTGF, and VEGF. Therefore, we suggest Trichosanthes kirilowii extract as a new component for skin care and as a wound-healing substance.

Utilizing Red Spotted Apollo Butterfly Transcriptome to Identify Antimicrobial Peptide Candidates against Porphyromonas gingivalis.

Classical antibiotics are the foremost treatment strategy against microbial infections. Overuse of this has led to the evolution of antimicrobial resistance. Antimicrobial peptides (AMPs) are natural defense elements present across many species including humans, insects, bacteria, and plants. Insect AMPs are our area of interest, because of their stronger abilities in host defense. We have deciphered AMPs from an endangered species Parnassius bremeri, commonly known as the red spotted apollo butterfly. It belongs to the second largest insect order Lepidoptera, comprised of butterflies and moths, and lives in the high altitudes of Russia, China, and Korea. We aimed at identifying the AMPs from the larvae stages. The rationale of choosing this stage is that the P. bremeri larvae development occurs at extremely low temperature conditions, which might serve as external stimuli for AMP production. RNA was isolated from larvae (L1 to L5) instar stages and subjected to next generation sequencing. The transcriptomes obtained were curated in in-silico pipelines. The peptides obtained were screened for requisite AMP physicochemical properties and in vitro antimicrobial activity. With the sequential screening and validation, we obtained fifteen candidate AMPs. One peptide TPS-032 showed promising antimicrobial activity against Porphyromonas gingivalis, a primary causative organism of periodontitis.

Antifungal Activity of 1,4-Dialkoxynaphthalen-2-Acyl Imidazolium Salts by Inducing Apoptosis of Pathogenic Candida spp.

Even though Candida spp. are staying commonly on human skin, it is also an opportunistic pathogenic fungus that can cause candidiasis. The emergence of resistant Candida strains and the toxicity of antifungal agents have encouraged the development of new classes of potent antifungal agents. Novel naphthalen-2-acyl imidazolium salts (NAIMSs), especially 1,4-dialkoxy-NAIMS from 1,4-dihydroxynaphthalene, were prepared and evaluated for antifungal activity. Those derivatives showed prominent anti-Candida activity with a minimum inhibitory concentration (MIC) of 3.125 to 6.26 µg/mL in 24 h based on microdilution antifungal susceptibility test. Among the tested compounds, NAIMS 7c showed strongest antifungal activity with 3.125 µg/mL MIC value compared with miconazole which showed 12.5 µg/mL MIC value against Candida spp., and more importantly >100 µg/mL MIC value against C. auris. The production of reactive oxygen species (ROS) was increased and JC-1 staining showed the loss of mitochondrial membrane potential in C. albicans by treatment with NAIMS 7c. The increased release of ultraviolet (UV) absorbing materials suggested that NAIMS 7c could cause cell busting. The expression of apoptosis-related genes was induced in C. albicans by NAIMS 7c treatment. Taken together, the synthetic NAIMSs are of high interest as novel antifungal agents given further in vivo examination.

Gentisic Acid Stimulates Keratinocyte Proliferation through ERK1/2 Phosphorylation.

Keratinocyte proliferation is important for skin wound healing. The wound healing process includes blood clotting around the wound, removal of dead cells and pathogens through inflammation, and then re-epithelialization through proliferation and maturation. Proliferation assay was performed on acid natural compounds to identify candidates for natural-derived components of skin injury treatment. We found that gentisic acid promoted high cell proliferation activity compared with other compounds. Gentisic acid improved HaCaT cell proliferation by over 20% in MTT assay. Gentisic acid also had higher healing activity in an in vitro wound healing assay than allantoin as a positive control. Furthermore, we have identified how the treatment of gentisic acid can increase proliferation in the cell. Western blot analysis of proteins in the mitogen-activated protein (MAP) kinase signaling pathway showed that ERK1/2 phosphorylation was increased by gentisic acid treatment. Thus, our study indicates that gentisic acid promotes the proliferation of keratinocyte by phosphorylation of ERK1/2.

Antifungal activity of magnoflorine against Candida strains.

Candida albicans is a major invasive pathogen, and the development of strains resistant to conventional antifungal agents has been reported in recent years. We evaluated the antifungal activity of 44 compounds against Candida strains. Magnoflorine showed the highest growth inhibitory activity of the tested Candida strains, with a minimum inhibitory concentration (MIC) of 50 µg/mL based on microdilution antifungal susceptibility testing. Disk diffusion assay confirmed the antifungal activity of magnoflorine and revealed that this activity was stable over 3 days compared to those of berberine and cinnamaldehyde. Cytotoxicity testing showed that magnoflorine could potentially be used in a clinical setting because it didn't have any toxicity to HaCaT cells even in 200 µg/mL of treatment. Magnoflorine at 50 µg/mL inhibited 55.91 ± 7.17% of alpha-glucosidase activity which is required for normal cell wall composition and virulence of Candida albicans. Magnoflorine also reduced the formation of C. albicans' biofilm. Combined treatment with magnoflorine and miconazole decreased the amount of miconazole required to kill various Candida albicans. Therefore, magnoflorine is a good candidate lead compound for novel antifungal agents.

Promotion of Keratinocyte Proliferation by Tracheloside through ERK1/2 Stimulation.

Cell migration and proliferation are important for proper wound healing after skin injury. Recent studies have shown that compounds from plants could promote cell migration and proliferation. Tracheloside, which is a plant lignan, has been found to promote the growth of HaCaT cells over 40% compared to other compounds tested based on a cell proliferation assay. An in vitro scratch assay confirmed the healing activity of tracheloside (more than 2-fold increased healing activity after 24 hours of treatment compared with the control) and revealed that this activity is better than that of allantoin (1.2-fold increased after 24 hours of treatment compared with the control), a positive control. With western blot results, wound healing with tracheloside occurred through the phosphorylation of ERK1/2. Therefore, tracheloside is a good candidate to promote wound healing and could be developed as a therapeutic agent for wound treatment or used as a leading compound with higher activity.