Chaminade University of Honolulu

About: Chaminade University of Honolulu is a education organization based out in Honolulu, Hawaii, United States. It is known for research contribution in the topics: Population & Experiential learning. The organization has 164 authors who have published 223 publications receiving 5381 citations.

Differential Regulation of Calcium Signalling Pathways by Components of Piper methysticum ('Awa)

Abstract: Kava is a soporific, anxiolytic and relaxant in widespread ritual and recreational use throughout the Pacific. Traditional uses of kava by indigenous Pacific Island peoples reflect a complex pharmacopeia, centered on GABA-ergic effects of the well-characterized kavalactones. However, peripheral effects of kava suggest active components other than the CNS-targeted kavalactones. We have previously shown that immunocytes exhibit calcium mobilization in response to traditionally prepared kava extracts, and that the kavalactones do not induce these calcium responses. Here, we characterize the complex calcium-mobilizing activity of traditionally prepared and partially HPLC-purified kava extracts, noting induction of both calcium entry and store release pathways. Kava components activate intracellular store depletion of thapsigargin-sensitive and -insensitive stores that are coupled to the calcium release activated (CRAC) current, and cause calcium entry through non-store-operated pathways. Together with the pepper-like potency reported by kava users, these studies lead us to hypothesize that kava extracts contain one or more ligands for the transient receptor potential (TRP) family of ion channels. Indeed, TRP-like conductances are observed in kava-treated cells under patch clamp. Thus TRP-mediated cellular effects may be responsible for some of the reported pharmacology of kava.

Prebiotic Potential of Taro (Colocasia esculenta) to Modulate Gut Bacteria Composition and Short Chain Fatty Acid Production

Abstract: Taro (Colocasia esculenta) is a high fiber tuber that holds cultural and agricultural importance in the Pacific. The high fiber content offers potential as a dietary prebiotic through the presence of resistant starch (RS). RS aids gut bacteria in the production of short-chain fatty acids (SCFA), which have health benefits to the host. As such, this study aimed to investigate the effect of taro on gut bacteria composition and SCFA production through in vitro human digestion and fecal fermentation methodology. Five taro varieties (Bun Long, Mana Ulu, Moi, Kauai Lehua, Tahitian) were processed. RS concentration of taro was determined using Megazyme Resistant Starch kit. Taro samples were subjected to in vitro human digestion, replicating oral, gastric, small intestinal, and large intestinal phases. Digested taro samples were mixed with fresh human fecal slurries and fermented at 37°C for 24 hours. During fermentation, samples were collected at specific time points for analyzation of SCFA contents using gas chromatography and bacterial composition using 16S rRNA gene targeted amplicon sequencing. Tahitian variety had the highest RS concentration of 25.1%, with no significantly difference between Tahitian, Bun Long, and Moi varieties. All taro varieties exhibited statistically similar SCFA concentrations for 3-hydroxybutyric acid, acetic acid and propionic acid. Bun-Long, Tahitian, and Moi varieties exhibited significantly higher butyric acid levels than two other taro varieties. Butyric acid production had the highest correlation coefficient with RS concentration of 0.80. The bacterial community present in all taro varieties after 24 hours of fermentation was markedly different from that of the control communities, including shifts in both the Bacteriodes and Firmicutes phyla. Different taro varieties have varying RS concentrations that affect the production of SCFA in an in vitro human digestion and fecal fermentation. The production of health-promoting butyric acid shows a strong positive correlation with the resistant starch concentration of taro. Taro distinctly causes shifts after 24 hours of fecal fermentation in Bacteriodes and Firmicutes phyla. These results provide new insights into the modulation of gut microbiota through dietary interventions. USDA-NIFA Hatch C-Maīki, University of Hawaii.

Transcriptional and Functional Plasticity Induced by Chronic Insulin Exposure in a Mast Cell-Like Basophilic Leukemia Cell Model.

Abstract: Objective: Secretory granules (SG) and lipid bodies (LB) are the primary organelles that mediate functional responses in mast cells. SG contains histamine and matrix-active proteases, while LB are reservoirs of arachidonic acid and its metabolites, precursors for rapid synthesis of eicosanoids such as LTC4. Both of these compartments can be dynamically or ontologically regulated, with metabolic and immunological stimuli altering lipid body content and granule numbers responding to contextual signals from tissue. We previously described that chronic in vitro or in vivo hyperinsulinemia expands the LB compartment with a concomitant loss of SG capacity, suggesting that this ratio is dynamically regulated. The objective of the current study is to determine if chronic insulin exposure initiates a transcriptional program that biases model mast cells towards a lipogenic state with accompanying loss of secretory granule biogenesis. Methods: We used a basophilic leukemic cell line with mucosal mast cell-like features as a model system. We tested the hypothesis that chronic insulin exposure initiates a transcriptional program that biases these model mast cells towards a lipogenic state with accompanying loss of secretory granule biogenesis. Transcriptional arrays were used to map gene expression patterns. Biochemical, immunocytochemical and mediator release assays were used to evaluate organelle numbers and functional responses. Results: In a mucosal mast cell model, the rat basophilic leukemia line RBL2H3, mast cell granularity and SG numbers are inversely correlated with LB numbers. Chronic insulin exposure appears to modulate gene networks involved in both lipid body biogenesis and secretory granule formation. Western blot analysis confirms upregulation of protein levels for LB proteins, and decreases in proteins that are markers for SG cargo. Conclusions: The levels of insulin in the extracellular milieu may modify the phenotype of mast cell-like cells in vitro.

Intergenerational Shared Sites in Hawaii

Abstract: Hawaii is often referred to as “the melting pot of the Pacific.” Multicultural diversity is embedded in the DNA of the state and its residents. Two Hawaii-based shared site programs, the Seagull Sc...