Chemical Composition of Essential Oil from Citrus reticulata Blanco cv. Chachiensis (Chachi) and Its Anti-Mosquito Activity against Pyrethroid-Resistant Aedes albopictus.

The overuse of synthetic insecticides has led to various negative consequences, including insecticide resistance, environmental pollution, and harm to public health. This may be ameliorated by using insecticides derived from botanical sources. The primary objective of this study was to evaluate the anti-mosquito activity of the essential oil (EO) of Citrus reticulata Blanco cv. Chachiensis (Chachi) (referred to as CRB) at immature, semi-mature, and mature stages. The chemical compositions of the CRB EO were analyzed using GC-MS. The main components were identified to be D-limonene and γ-terpinene. The contents of D-limonene at the immature, semi-mature, and mature stages were 62.35%, 76.72%, and 73.15%, respectively; the corresponding contents of γ-terpinene were 14.26%, 11.04%, and 11.27%, respectively. In addition, the corresponding contents of a characteristic component, methyl 2-aminobenzoate, were 4.95%, 1.93%, and 2.15%, respectively. CRB EO exhibited significant larvicidal activity against Aedes albopictus (Ae. albopictus, Diptera: Culicidae), with the 50% lethal doses being 65.32, 61.47, and 65.91 mg/L for immature, semi-mature, and mature CRB EO, respectively. CRB EO was able to inhibit acetylcholinesterase and three detoxification enzymes, significantly reduce the diversity of internal microbiota in mosquitoes, and decrease the relative abundance of core species within the microbiota. The present results may provide novel insights into the utilization of plant-derived essential oils in anti-mosquitoes.

Bipiperidinyl Derivatives of Cannabidiol Enhance Its Antiproliferative Effects in Melanoma Cells.

Cannabis and its major cannabinoid cannabidiol (CBD) are reported to exhibit anticancer activity against skin tumors. However, the cytotoxic effects of other minor cannabinoids and synthetic CBD derivatives in melanoma are not fully elucidated. Herein, the antiproliferative activity of a panel of phytocannabinoids was screened against murine (B16F10) and human (A375) melanoma cells. CBD was the most cytotoxic natural cannabinoid with respective IC50 of 28.6 and 51.6 µM. Further assessment of the cytotoxicity of synthetic CBD derivatives in B16F10 cells identified two bipiperidinyl group-bearing derivatives (22 and 34) with enhanced cytotoxicity (IC50 = 3.1 and 8.5 µM, respectively). Furthermore, several cell death assays including flow cytometric (for apoptosis and ferroptosis) and lactate dehydrogenase (for pyroptosis) assays were used to characterize the antiproliferative activity of CBD and its bipiperidinyl derivatives. The augmented cytotoxicity of 22 and 34 in B16F10 cells was attributed to their capacity to promote apoptosis (as evidenced by increased apoptotic population). Taken together, this study supports the notion that CBD and its derivatives are promising lead compounds for cannabinoid-based interventions for melanoma management.

One-Step Synthesis of Hydrogel Adhesive with Acid-Responsive Tannin Release for Diabetic Oral Mucosa Defects Healing.

The complex preparation, weak wet tissue adhesion, and limited biological activity of traditional oral wound dressings usually impede their efficient treatment and healing for diabetic oral mucosal defects. To overcome these problems, a novel hydrogel adhesive (named CFT hydrogel) is rapidly constructed using a one-step method based on dual-dynamic covalent cross-linking. Compared with the commercial oral patches, the CFT hydrogel shows superior in vivo (rat tongue) wet tissue adhesion performance. Additionally, the CFT hydrogel exhibits unique acid-responsive properties, thereby facilitating the release of bioactive molecule tannic acid in the acidic diabetic wound microenvironment. And a series of in vitro experiments substantiate the favorable biocompatibility and bioactivity properties (including antibacterial, antioxidative, anti-inflammatory, and angiogenetic effects) exhibited by CFT hydrogel. Moreover, in vivo experiments conducted on a diabetic rat model with oral mucosal defects demonstrate that the CFT hydrogel exhibits significant efficacy in protecting against mucosal wounds, alleviating inflammatory reactions, thereby facilitating the wound-healing process. Taken together, this study provides a promising and comprehensive therapeutic option with great potential for the clinical management of oral mucosa defects in diabetic patients.

Inhibitory effect of liriopesides B in combination with gemcitabine on human pancreatic cancer cells.

Gemcitabine (GEM) is a standard chemotherapeutic agent for patients with pancreatic cancer; however, GEM-based chemotherapy has a high rate of toxicity. A combination of GEM and active constituents from natural products may enhance its therapeutic efficacy and reduce its toxicity. This study investigated the synergistic effects of the combination of liriopesides B (LirB) from Liriope spicata var. prolifera and GEM on human pancreatic cancer cells. The results of our study showed that the combination of LirB and GEM synergistically decreased the viability of pancreatic cancer cells. The combination also caused a strong increase in apoptosis and a strong decrease in cell migration and invasion. Furthermore, LirB combined with GEM had potent inhibitory effects on pancreatic cancer stem cells (CSCs). Studies on the mechanisms of action showed that the combination more potently inhibited protein kinase B (Akt) and nuclear factor kappa B (NF-κB), as well as the downstream antiapoptotic molecules B-cell lymphoma 2 (Bcl-2) and survivin than either agent used alone. The results of this study suggest that the combination of LirB with GEM may improve the efficacy of GEM for the treatment of pancreatic cancer.